I have this signature view that enables you to basically draw on phones screen. Now I need to add this view as a background or use it like a widget on a xml layout but I have no idea how to do that. So please can anybody help me do this.
This is the signature view class that I have:
import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;
public class SignatureView extends View {
private static final float STROKE_WIDTH = 5f;
/** Need to track this so the dirty region can accommodate the stroke. **/
private static final float HALF_STROKE_WIDTH = STROKE_WIDTH / 2;
private Paint paint = new Paint();
private Path path = new Path();
/**
* Optimizes painting by invalidating the smallest possible area.
*/
private float lastTouchX;
private float lastTouchY;
private final RectF dirtyRect = new RectF();
public SignatureView(Context context, AttributeSet attrs, int background) {
super(context, attrs);
setBackgroundResource(background);
paint.setAntiAlias(true);
paint.setColor(Color.BLACK);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeJoin(Paint.Join.ROUND);
paint.setStrokeWidth(STROKE_WIDTH);
}
public void setColor(int color){
paint.setColor(color);
}
/**
* Erases the signature.
*/
public void clear() {
path.reset();
// Repaints the entire view.
invalidate();
}
#Override
protected void onDraw(Canvas canvas) {
canvas.drawPath(path, paint);
}
#Override
public boolean onTouchEvent(MotionEvent event) {
float eventX = event.getX();
float eventY = event.getY();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
path.moveTo(eventX, eventY);
lastTouchX = eventX;
lastTouchY = eventY;
// There is no end point yet, so don't waste cycles invalidating.
return true;
case MotionEvent.ACTION_MOVE:
case MotionEvent.ACTION_UP:
// Start tracking the dirty region.
resetDirtyRect(eventX, eventY);
// When the hardware tracks events faster than they are delivered, the
// event will contain a history of those skipped points.
int historySize = event.getHistorySize();
for (int i = 0; i < historySize; i++) {
float historicalX = event.getHistoricalX(i);
float historicalY = event.getHistoricalY(i);
expandDirtyRect(historicalX, historicalY);
path.lineTo(historicalX, historicalY);
}
// After replaying history, connect the line to the touch point.
path.lineTo(eventX, eventY);
break;
default:
// Log.("Ignored touch event: " + event.toString());
return false;
}
// Include half the stroke width to avoid clipping.
invalidate(
(int) (dirtyRect.left - HALF_STROKE_WIDTH),
(int) (dirtyRect.top - HALF_STROKE_WIDTH),
(int) (dirtyRect.right + HALF_STROKE_WIDTH),
(int) (dirtyRect.bottom + HALF_STROKE_WIDTH));
lastTouchX = eventX;
lastTouchY = eventY;
return true;
}
/**
* Called when replaying history to ensure the dirty region includes all
* points.
*/
private void expandDirtyRect(float historicalX, float historicalY) {
if (historicalX < dirtyRect.left) {
dirtyRect.left = historicalX;
} else if (historicalX > dirtyRect.right) {
dirtyRect.right = historicalX;
}
if (historicalY < dirtyRect.top) {
dirtyRect.top = historicalY;
} else if (historicalY > dirtyRect.bottom) {
dirtyRect.bottom = historicalY;
}
}
/**
* Resets the dirty region when the motion event occurs.
*/
private void resetDirtyRect(float eventX, float eventY) {
// The lastTouchX and lastTouchY were set when the ACTION_DOWN
// motion event occurred.
dirtyRect.left = Math.min(lastTouchX, eventX);
dirtyRect.right = Math.max(lastTouchX, eventX);
dirtyRect.top = Math.min(lastTouchY, eventY);
dirtyRect.bottom = Math.max(lastTouchY, eventY);
}
}
and my main class:
public class Draw extends Activity {
DrawView drawView;
SignatureView signature;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Set full screen view
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
requestWindowFeature(Window.FEATURE_NO_TITLE);
signature = new SignatureView(this, null,R.drawable.back);
setContentView(signature);
signature.requestFocus();
}
public boolean onCreateOptionsMenu(Menu menu) {
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.my_options_menu, menu);
return true;
}
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.clear:
signature.clear();
return true;
case R.id.red:
signature.setColor(Color.RED);
return true;
case R.id.blue:
signature.setColor(Color.BLUE);
return true;
case R.id.yellow:
signature.setColor(Color.YELLOW);
return true;
default:
return super.onOptionsItemSelected(item);
}
}
#Override
public void onBackPressed() {
this.finish();
super.onBackPressed();
}
}
You'll reference this in your XML layouts by the full name, such as com.example.myapp.SignatureView.
<com.example.myapp.SignatureView android:id="#+id\my_id"
android:layout_width="match_parent"
android:layout_height="match_parent">
</com.example.myapp.SignatureView>
You can reference this in the code behind normally as well
SignatureView sv = (SignatureView)findViewById(R.id.my_id);
sv.setColor(Color.RED);
To add it to the xml, you add a tag like this <com.example.SignatureView /> where the com.example stuff is replaced by your package name. You can add parameters and sub-tabs as normal.
Related
I have seen a lots of code here which is helpful to zoom your textview but none of them work with my text because it is within scrollview. How can I get rid of this problem?
import android.app.Activity;
import android.os.Bundle;
import android.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.TextView;
public class Introduce extends Activity implements OnTouchListener{
final static float STEP = 200;
TextView mtxtRatio1,mtxtRatio2,mtxtRatio3,mtxtRatio4;
float mRatio = 1.0f;
int mBaseDist;
float mBaseRatio;
float fontsize = 13;
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.introduce);
mtxtRatio1 = (TextView)findViewById(R.id.intro1);
mtxtRatio1.setTextSize(mRatio+13);
}
public boolean onTouchEvent(MotionEvent event) {
if (event.getPointerCount() == 2) {
int action = event.getAction();
int pureaction = action & MotionEvent.ACTION_MASK;
if (pureaction == MotionEvent.ACTION_POINTER_DOWN) {
mBaseDist = getDistance(event);
mBaseRatio = mRatio;
} else {
float delta = (getDistance(event) - mBaseDist) / STEP;
float multi = (float)Math.pow(2, delta);
mRatio = Math.min(1024.0f, Math.max(0.1f, mBaseRatio * multi));
mtxtRatio1.setTextSize(mRatio+13);
}
}
return true;
}
int getDistance(MotionEvent event) {
int dx = (int)(event.getX(0) - event.getX(1));
int dy = (int)(event.getY(0) - event.getY(1));
return (int)(Math.sqrt(dx * dx + dy * dy));
}
public boolean onTouch(View v, MotionEvent event) {
// TODO Auto-generated method stub
return false;
}
}
Following is the way for implementing Pinch Zoom in TextView with/without ScrollView
MainActivity.java
public class MainActivity extends AppCompatActivity{
final static float STEP = 200;
float mRatio = 1.0f;
int mBaseDist;
float mBaseRatio;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
textViewData = (TextView).findViewById(R.id.tvContributeData);
textViewData.setOnTouchListener(new View.OnTouchListener() {
#Override
public boolean onTouch(View view, MotionEvent event) {
if (event.getPointerCount() == 2) {
int action = event.getAction();
int pureaction = action & MotionEvent.ACTION_MASK;
if (pureaction == MotionEvent.ACTION_POINTER_DOWN) {
mBaseDist = getDistance(event);
mBaseRatio = mRatio;
} else {
float delta = (getDistance(event) - mBaseDist) / STEP;
float multi = (float) Math.pow(2, delta);
mRatio = Math.min(1024.0f, Math.max(0.1f, mBaseRatio * multi));
textViewData.setTextSize(mRatio + 13);
}
}
return true;
});
int getDistance(MotionEvent event) {
int dx = (int) (event.getX(0) - event.getX(1));
int dy = (int) (event.getY(0) - event.getY(1));
return (int) (Math.sqrt(dx * dx + dy * dy));
}
}
}
Use Polidea's zoomview, it works in a scrollview and has pinch zoom and double tap to zoom, one thing thought, I ended up disabling the pinch zoom and just using the double tap
https://github.com/Polidea/android-zoom-view
Put your TextView andany other Views you are using into a LinearLayout that lives on a ZoomView which lives on the ScrollView, e.g.:
<ScrollView
android:layout_width="match_parent"
android:layout_height="wrap_content">
<com.polidea.ZoomView
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:id="#+id/myLinearLayout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical" >
</LinearLayout>
</com.polidea.ZoomView>
</ScrollView>
Hopefully this will help others. This answer is from here and here.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView) findViewById(R.id.tv);
tv.setText(getString(R.string.hello_world));
scaleGestureDetector = new ScaleGestureDetector(this, new simpleOnScaleGestureListener());
tv.setOnTouchListener(new OnTouchListener() {
#Override
public boolean onTouch(View v, MotionEvent event) {
if(event.getPointerCount() == 1){
//stuff for 1 pointer
}else{ //when 2 pointers are present
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
// Disallow ScrollView to intercept touch events.
v.getParent().requestDisallowInterceptTouchEvent(true);
scaleGestureDetector.onTouchEvent(event);
break;
case MotionEvent.ACTION_MOVE:
// Disallow ScrollView to intercept touch events.
v.getParent().requestDisallowInterceptTouchEvent(true);
scaleGestureDetector.onTouchEvent(event);
break;
case MotionEvent.ACTION_UP:
// Allow ScrollView to intercept touch events.
v.getParent().requestDisallowInterceptTouchEvent(false);
break;
}
}
return true;
}
});
}
The answer from here has the problem when text is resized even fingers are static (two fingers on the screen). What I did is add a check so that the textSize do not make any changes instantly.
private float safe;
public class simpleOnScaleGestureListener extends SimpleOnScaleGestureListener {
#Override
public boolean onScale(ScaleGestureDetector detector) {
// TODO Auto-generated method stub
float size = tv.getTextSize();
Log.d("TextSizeStart", String.valueOf(size));
//float factor = detector.getScaleFactor();
float factor = Math.max(0.5f, Math.min(detector.getScaleFactor(), 2f));
Log.d("Factor", String.valueOf(factor));
float product = size*factor;
Log.d("TextSize", String.valueOf(product));
safe = Math.abs(product - size);
if(product <= 100 && product >= 20 && safe < 3){
//tv.setText("factor= " +factor + "\n" + "product = \n" + size + " * " + factor + " \n= " + product +"\n" + getString(R.string.hello_world));
tv.setTextSize(TypedValue.COMPLEX_UNIT_PX, product);
}
size = tv.getTextSize();
Log.d("TextSizeEnd", String.valueOf(size));
return true;
}
}
You can play around with safe < 3 to your desired changes value.
I'm using this solution.
Crédits for Zoom Algorithm in this vídeo
Use a TextView without ScrollView, just use android:scrollbars="vertical"
<TextView
android:id="#+id/activity_content_text_content"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_weight="1"
android:gravity="fill"
android:textSize="8pt"
android:scrollbars="vertical"
/>
Java:
public class MainActivity extends Activity implements View.OnTouchListener {
private TextView textContent = null;
private final static float move = 200;
private float ratio = 1.0f;
private int baseDist;
private float baseRatio;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.teste_layout);
textContent = findViewById(R.id.activity_content_text_content);
textContent.setText("Lorem ipsum dolor sit amet......");
textContent.setMovementMethod(new ScrollingMovementMethod());
textContent.setOnTouchListener(this);
}
#Override
public boolean onTouch(View v, MotionEvent event) {
return onTouchEvent(event);
}
#Override
public boolean onTouchEvent(MotionEvent event) {
if(event.getPointerCount() == 2){
int action = event.getAction();
int mainAction = action&MotionEvent.ACTION_MASK;
if(mainAction == MotionEvent .ACTION_POINTER_DOWN){
baseDist = getDisTance(event);
baseRatio = ratio;
} else {
float scale = (getDisTance(event)-baseDist)/move;
float factor = (float)Math.pow(2, scale);
ratio = Math.min(1024.0f, Math.max(0.1f, baseRatio*factor));
textContent.setTextSize(ratio+15);
}
} else {
return false;
}
return true;
}
private int getDisTance(MotionEvent event) {
int dx = (int) (event.getX(0)-event.getX(1));
int dy = (int) (event.getY(0)-event.getY(1));
return (int) (Math.sqrt(dx*dx+dy*dy));
}
}
Goal
An activity is made to view image, we can pinch zoom or pan the image. The image is centered in the screen in the beginning. Pinch zoom is centered at the center of the image, even after the image is panned somewhere else in the screen.
The image for displaying is downloaded from a given URL, and the URL is passed from extra of an intent to start the image viewing activity.
Pinch zoom is implemented by postScale(), pan by postTranslate().
Problem
After panning the image somewhere, the pinch-zoom center is still at the center of the screen. Tried to follow the center of the image when it's been moved to a new place but my code doesn't work that way. Please give some idea.
The image downloading and panning work well.
Code
activity_image_viewer_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center"
android:background="#color/MyPureBlack" >
<LinearLayout
android:id="#+id/progressbar_wrapper"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<ProgressBar
android:id="#+id/progressbar"
style="?android:attr/progressBarStyleHorizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:max="100"
android:progress="0"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:layout_gravity="center" >
</ProgressBar>
</LinearLayout>
<ImageView
android:id="#+id/image_viewer"
android:visibility="gone"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#color/MyPureBlack"
android:scaleType="matrix" >
</ImageView>
</LinearLayout>
</FrameLayout>
ActivityImageViewer.java
package com.com2us.hubapp.android;
import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.URL;
import java.net.URLConnection;
import org.apache.http.util.ByteArrayBuffer;
import android.app.Activity;
import android.content.res.Configuration;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.graphics.Rect;
import android.graphics.RectF;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Bundle;
import android.util.FloatMath;
import android.util.Log;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.view.ViewTreeObserver;
import android.view.ViewTreeObserver.OnGlobalLayoutListener;
import android.view.animation.AlphaAnimation;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ProgressBar;
public class ActivityImageViewer extends Activity {
File imageFile = null;
// Matrices for pinch zoom and pan
Matrix matrix = new Matrix();
Matrix savedMatrix = new Matrix();
Matrix savedMatrixZoom = new Matrix();
// State of motion event
static final int NONE = 0;
static final int PAN = 1;
static final int PINCH_ZOOM = 2;
int mode = NONE;
// The first pointer down
PointF start = new PointF();
// The center of the image (Failed to track it when the image has been moved)
PointF centerOfImage = new PointF();
// oldest is the Cartesian distance between first two pointers when the second pointer is down
float oldDist = 1f;
// MIN_SCALE/MAX_SCALE is the min/max scale factor
private final float MIN_SCALE = 0.5f;
private final float MAX_SCALE = 3.0f;
// TOUCH_SENSITIVE is the minimum Cartesian distance between the first two pointers that triggers the pinch zoom
private final float TOUCH_SENSITIVE = 10.0f;
private final float SPACING_LEFT_AND_RIGHT = 30.0f;
private final float SPACING_TOP_AND_BOTTOM = 30.0f;
// The ImageView widget
private ImageView image_viewer;
// The progress bar shows what current progress is before the image downloading is completed
private ProgressBar progressbar;
private LinearLayout progressbar_wrapper;
// An async task that downloads the image from a given URL
private DownloadFilesTask downloadFilesTask;
private class DownloadFilesTask extends AsyncTask<String, Integer, Bitmap> {
protected Bitmap doInBackground(String... urls) {
InputStream input = null;
OutputStream output = null;
try {
URL url = new URL(urls[0]);
URLConnection connection = url.openConnection();
connection.connect();
int lenghtOfFile = connection.getContentLength();
// download the file
InputStream is = connection.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is, 8190);
ByteArrayBuffer baf = new ByteArrayBuffer(50);
int current = 0;
while ((current = bis.read()) != -1) {
baf.append((byte)current);
}
byte[] imageData = baf.toByteArray();
Bitmap bmp = BitmapFactory.decodeByteArray(imageData, 0, imageData.length);
//final int percent = (int) (total * 100 / lenghtOfFile);
//publishProgress(percent);
//lenghtOfFile
return bmp;
} catch (Exception e) {
} finally {
try {
if (output != null)
output.close();
output = null;
} catch (IOException e) {
}
try {
if (input != null)
input.close();
input = null;
} catch (IOException e) {
}
}
return null;
} // protected Bitmap doInBackground(String... urls) {}
protected void onProgressUpdate(Integer... progress) {
progressbar.setProgress(progress[0]);
}
protected void onPostExecute(Bitmap bmp) {
if (bmp != null) {
final AlphaAnimation animationAfter = new AlphaAnimation(0.0f, 1.0f);
animationAfter.setDuration(300);
animationAfter.setFillEnabled(true);
animationAfter.setFillAfter(true);
image_viewer.setAnimation(animationAfter);
image_viewer.setImageBitmap(bmp);
ViewTreeObserver viewTreeObserver = image_viewer.getViewTreeObserver();
viewTreeObserver.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
Drawable drawable = image_viewer.getDrawable();
int dx = (image_viewer.getWidth() - drawable.getIntrinsicWidth()) / 2;
int dy = (image_viewer.getHeight() - drawable.getIntrinsicHeight()) / 2;
matrix.postTranslate(dx, dy);
image_viewer.setImageMatrix(matrix);
}
});
progressbar_wrapper.setVisibility(View.GONE);
image_viewer.setVisibility(View.VISIBLE);
} else {
android.os.Handler handler = new android.os.Handler();
handler.postDelayed(new Runnable() {
#Override
public void run() {
finish();
}
}, 2000);
}
} // End of protected void onPostExecute(Bitmap bmp) {}
} // End of private class DownloadFilesTask extends AsyncTask<String, Integer, Bitmap> {}
// These are activity life cycle handling
// onCreate
#Override
public void onCreate(Bundle savedInstanceState) {
//setTheme(R.style.HubTheme);
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_image_viewer);
progressbar_wrapper = (LinearLayout) findViewById(R.id.progressbar_wrapper);
image_viewer = (ImageView) findViewById(R.id.image_viewer);
progressbar = (ProgressBar) findViewById(R.id.progressbar);
image_viewer.setOnTouchListener(new MyOnTouchListener());
final String uriForImage = getIntent().getStringExtra("url");
downloadFilesTask = new DownloadFilesTask();
downloadFilesTask.execute(uriForImage);
}
// onStart
#Override
protected void onStart() {
super.onStart();
}
// onResume
#Override
protected void onResume() {
super.onResume();
}
// onPause
#Override
protected void onPause() {
super.onPause();
}
// onStop
#Override
protected void onStop() {
super.onStop();
}
// onRestart
#Override
protected void onRestart() {
super.onRestart();
}
// onDestroy
#Override
protected void onDestroy() {
super.onDestroy();
if (imageFile != null) {
try {
Drawable drawable = image_viewer.getDrawable();
BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable;
Bitmap bitmap = bitmapDrawable.getBitmap();
bitmap.recycle();
drawable = null;
bitmapDrawable = null;
bitmap = null;
} catch (NullPointerException e) {
}
}
}
// onKeyDown
#Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_BACK) {
this.onBackPressed();
}
return true;
}
// onBackPressed
public void onBackPressed() {
finish();
}
// onConfigurationChanged
#Override
public void onConfigurationChanged(Configuration newConfig) {
super.onConfigurationChanged(newConfig);
if (newConfig.equals(Configuration.ORIENTATION_LANDSCAPE)) {
} else if (newConfig.equals(Configuration.ORIENTATION_PORTRAIT)) {
}
}
// onLowMemory
#Override
public void onLowMemory() {
super.onLowMemory();
finish();
}
// Get the Cartesian distance between the first two pointers
private float spacing(MotionEvent event) {
float x = 0;
float y = 0;
try {
Method getX = MotionEvent.class.getMethod("getX", Integer.TYPE);
Method getY = MotionEvent.class.getMethod("getX", Integer.TYPE);
// x = event.getX(0) - event.getX(1);
// y = event.getY(0) - event.getY(1);
float x1 = (Float) getX.invoke(event, 0);
float x2 = (Float) getX.invoke(event, 1);
x = x1 - x2;
float y1 = (Float) getY.invoke(event, 0);
float y2 = (Float) getY.invoke(event, 1);
y = y1 - y2;
} catch (SecurityException e) {
} catch (NoSuchMethodException e) {
} catch (IllegalArgumentException e) {
} catch (IllegalAccessException e) {
} catch (InvocationTargetException e) {
}
return FloatMath.sqrt(x * x + y * y);
}
// Some flags set manually for convenience
private final int MotionEvent_ACTION_MASK = 255; // that is 0xFF or 11111111
private final int MotionEvent_ACTION_POINTER_DOWN = 5; // that is 101
private final int MotionEvent_ACTION_POINTER_UP = 6; // that is 110
private class MyOnTouchListener implements OnTouchListener {
// onTouch
#Override
public boolean onTouch(View v, MotionEvent event) {
ImageView view = (ImageView) v;
Drawable drawable = view.getDrawable();
if (drawable == null)
return true;
switch (event.getAction() & MotionEvent_ACTION_MASK) {
case MotionEvent.ACTION_DOWN:
savedMatrix.set(matrix);
start.set(event.getX(), event.getY());
mode = PAN;
break;
case MotionEvent_ACTION_POINTER_DOWN:
oldDist = spacing(event);
if (oldDist > TOUCH_SENSITIVE) {
savedMatrix.set(matrix);
mode = PINCH_ZOOM;
}
break;
case MotionEvent.ACTION_UP:
case MotionEvent_ACTION_POINTER_UP:
mode = NONE;
break;
case MotionEvent.ACTION_MOVE:
if (mode == PAN) {
// /////////////////////////////////////////
matrix.set(savedMatrix);
float[] matrixValues = new float[9];
Rect viewRect = new Rect(view.getLeft(), view.getTop(), view.getRight(), view.getBottom());
matrix.getValues(matrixValues);
float currentY = matrixValues[Matrix.MTRANS_Y];
float currentX = matrixValues[Matrix.MTRANS_X];
float currentScale = matrixValues[Matrix.MSCALE_X];
float currentHeight = drawable.getIntrinsicHeight() * currentScale;
float currentWidth = drawable.getIntrinsicWidth() * currentScale;
float dx = event.getX() - start.x;
float dy = event.getY() - start.y;
float newX = currentX + dx;
float newY = currentY + dy;
RectF drawingRect = new RectF(newX, newY, newX + currentWidth, newY + currentHeight);
float diffUp = Math.min(viewRect.bottom - drawingRect.bottom, viewRect.top - drawingRect.top) - SPACING_TOP_AND_BOTTOM;
float diffDown = Math.max(viewRect.bottom - drawingRect.bottom, viewRect.top - drawingRect.top) + SPACING_TOP_AND_BOTTOM;
float diffLeft = Math.min(viewRect.left - drawingRect.left, viewRect.right - drawingRect.right) - SPACING_LEFT_AND_RIGHT;
float diffRight = Math.max(viewRect.left - drawingRect.left, viewRect.right - drawingRect.right) + SPACING_LEFT_AND_RIGHT;
if (diffUp > 0) {
dy += diffUp;
}
if (diffDown < 0) {
dy += diffDown;
}
if (diffLeft > 0) {
dx += diffLeft;
}
if (diffRight < 0) {
dx += diffRight;
}
matrix.postTranslate(dx, dy);
} else if (mode == PINCH_ZOOM) {
float newDist = spacing(event);
if (newDist > TOUCH_SENSITIVE) {
matrix.set(savedMatrix);
float scale = newDist / oldDist;
// Get the center of the image. (Failed to get it when image has been moved)
Rect viewRect = new Rect(view.getLeft(), view.getTop(), view.getRight(), view.getBottom());
centerOfImage.x = viewRect.centerX();
centerOfImage.y = viewRect.centerY();
float[] f = new float[9];
Matrix tmp = new Matrix(matrix);
tmp.postScale(scale, scale, centerOfImage.x, centerOfImage.y);
tmp.getValues(f);
float scaleX = f[Matrix.MSCALE_X];
if (scaleX < MIN_SCALE || scaleX > MAX_SCALE) {
matrix.set(savedMatrixZoom);
} else {
matrix.postScale(scale, scale, centerOfImage.x, centerOfImage.y);
savedMatrixZoom.set(matrix);
}
}
}
break;
}
view.setImageMatrix(matrix);
return true;
} // End of public boolean onTouch(View v, MotionEvent event) {}
} // End of private class MyOnTouchListener implements OnTouchListener {}
} // End of public class ActivityImageViewer extends Activity {}
You can use the Scale Gesture Detector for pinch to zoom. Instead of creating pinch to zoom from scratch you can do something like following,
public class MyCustomView extends View {
private ScaleGestureDetector mScaleDetector;
private float mScaleFactor = 1.f;
public MyCustomView(Context mContext){
...
// View code goes here
...
mScaleDetector = new ScaleGestureDetector(context, new ScaleListener());
}
#Override
public boolean onTouchEvent(MotionEvent ev) {
// Let the ScaleGestureDetector inspect all events.
mScaleDetector.onTouchEvent(ev);
return true;
}
#Override
public void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.save();
canvas.scale(mScaleFactor, mScaleFactor);
...
// onDraw() code goes here
...
canvas.restore();
}
private class ScaleListener
extends ScaleGestureDetector.SimpleOnScaleGestureListener {
#Override
public boolean onScale(ScaleGestureDetector detector) {
mScaleFactor *= detector.getScaleFactor();
// Don't let the object get too small or too large.
mScaleFactor = Math.max(0.1f, Math.min(mScaleFactor, 5.0f));
invalidate();
return true;
}
}
}
Note : Your translation will reside in onDraw method to scale an image.
i have a bus route map as an image.
using the zoom controller the image is zooming out but not zooming in
please look at my code and let me know the change to be done make it working..
i am developing my app on Gingerbread i.e API 10
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.widget.ZoomControls;
public class Busmaps extends Activity {
ImageView img;
ZoomControls zoom;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.busmaps);
img = (ImageView) findViewById(R.id.imageViewmaps1);
zoom = (ZoomControls) findViewById(R.id.zoomControls1);
zoom.setOnZoomInClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
int w = img.getWidth();
int h = img.getHeight();
RelativeLayout.LayoutParams params =
new RelativeLayout.LayoutParams(w + 50, h + 50);
params.addRule(RelativeLayout.CENTER_IN_PARENT);
img.setLayoutParams(params);
}
});
zoom.setOnZoomOutClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
int w = img.getWidth();
int h = img.getHeight();
RelativeLayout.LayoutParams params =
new RelativeLayout.LayoutParams(w - 50, h - 50);
params.addRule(RelativeLayout.CENTER_IN_PARENT);
img.setLayoutParams(params);
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.bus_map_zoom, menu);
return true;
}
}
my xml says for bus route image:-
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<ImageView
android:id="#+id/imageViewmaps1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:src="#drawable/map" />
<ZoomControls
android:id="#+id/zoomControls1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
/>
</RelativeLayout>
how should i make my zoom control working for both Zoom in and Zoom out.
Please replace your Zoom in and ZoomOut listener with the following:
zoom.setOnZoomInClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
float x = img.getScaleX();
float y = img.getScaleY();
img.setScaleX((float) (x+1));
img.setScaleY((float) (y+1));
}
});
zoom.setOnZoomOutClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// TODO Auto-generated method stub
float x = img.getScaleX();
float y = img.getScaleY();
img.setScaleX((float) (x-1));
img.setScaleY((float) (y-1));
}
});
}
Alternate option is to load the image in the Web view which has build in zoom controller.
As follows:
String page = "<html><body><center><img src=\""+path to your image+"\"/></center></body></html>";
webView.loadDataWithBaseURL("fake",page, "text/html", "UTF-8","");
If you dont want to use the build in web view zoom controller then you can just place your own buttons and apply zoom in and zoom out on web view as follows:
webView.setInitialScale(ZOOM_LEVEL);
public class Busmap extends Activity implements OnTouchListener
{
private static final String TAG = "Touch";
#SuppressWarnings("unused")
private static final float MIN_ZOOM = 1f,MAX_ZOOM = 1f;
// These matrices will be used to scale points of the image
Matrix matrix = new Matrix();
Matrix savedMatrix = new Matrix();
// The 3 states (events) which the user is trying to perform
static final int NONE = 0;
static final int DRAG = 1;
static final int ZOOM = 2;
int mode = NONE;
// these PointF objects are used to record the point(s) the user is touching
PointF start = new PointF();
PointF mid = new PointF();
float oldDist = 1f;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.busmaps);
ImageView view = (ImageView) findViewById(R.id.imageViewmaps1);
view.setOnTouchListener(this);
}
#Override
public boolean onTouch(View v, MotionEvent event)
{
ImageView view = (ImageView) v;
view.setScaleType(ImageView.ScaleType.MATRIX);
float scale;
dumpEvent(event);
// Handle touch events here...
switch (event.getAction() & MotionEvent.ACTION_MASK)
{
case MotionEvent.ACTION_DOWN: // first finger down only
savedMatrix.set(matrix);
start.set(event.getX(), event.getY());
Log.d(TAG, "mode=DRAG"); // write to LogCat
mode = DRAG;
break;
case MotionEvent.ACTION_UP: // first finger lifted
case MotionEvent.ACTION_POINTER_UP: // second finger lifted
mode = NONE;
Log.d(TAG, "mode=NONE");
break;
case MotionEvent.ACTION_POINTER_DOWN: // first and second finger down
oldDist = spacing(event);
Log.d(TAG, "oldDist=" + oldDist);
if (oldDist > 5f) {
savedMatrix.set(matrix);
midPoint(mid, event);
mode = ZOOM;
Log.d(TAG, "mode=ZOOM");
}
break;
case MotionEvent.ACTION_MOVE:
if (mode == DRAG)
{
matrix.set(savedMatrix);
matrix.postTranslate(event.getX() - start.x, event.getY() - start.y); // create the transformation in the matrix of points
}
else if (mode == ZOOM)
{
// pinch zooming
float newDist = spacing(event);
Log.d(TAG, "newDist=" + newDist);
if (newDist > 5f)
{
matrix.set(savedMatrix);
scale = newDist / oldDist; // setting the scaling of the
// matrix...if scale > 1 means
// zoom in...if scale < 1 means
// zoom out
matrix.postScale(scale, scale, mid.x, mid.y);
}
}
break;
}
view.setImageMatrix(matrix); // display the transformation on screen
return true; // indicate event was handled
}
private float spacing(MotionEvent event)
{
float x = event.getX(0) - event.getX(1);
float y = event.getY(0) - event.getY(1);
return FloatMath.sqrt(x * x + y * y);
}
private void midPoint(PointF point, MotionEvent event)
{
float x = event.getX(0) + event.getX(1);
float y = event.getY(0) + event.getY(1);
point.set(x / 2, y / 2);
}
I am a new beginner in android and I want to make a simple program that detect touch coordinates and draw a circle and path of touch, I make a simple program that draw a circle around the touch and follow it but I still can do the path of touch. When I start the program with path it crash, when I remove the path it works normal...
public class MainActivity extends Activity {
float x = 0;
float y = 0;
LinearLayout layout; //declarea variabilor pentru desenarea cercului
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main); //specificarea
layout = (LinearLayout)findViewById(R.id.layout); //gasirea id
layout.addView(new CustomView(MainActivity.this));
}
public class CustomView extends View { //crearea unei mape pentru canvas
Bitmap mBitmap;
Paint paint;
Path path;
public CustomView(Context context) {
super(context);
mBitmap = Bitmap.createBitmap(640, 1024, Bitmap.Config.ARGB_8888);
paint = new Paint();
path = new Path();
paint.setColor(Color.BLUE);//culoare cercului desenat
paint.setStyle(Style.FILL);
}
protected void onDraw(Canvas canvas) {//desenarea cercului la atingere
super.onDraw(canvas);
canvas.drawPath(path,paint);
canvas.drawCircle(x, y, 25, paint);
}
public boolean onTouchEvent(MotionEvent event) {
int action = event.getAction();
switch (action){
case MotionEvent.ACTION_DOWN:
path.moveTo(event.getX(), event.getY());
path.lineTo(event.getX(), event.getY());
break;
case MotionEvent.ACTION_MOVE:
x = event.getX();
y = event.getY();
path.lineTo(x, y);
invalidate();
break;
case MotionEvent.ACTION_UP:
path.lineTo(event.getX(), event.getY());
break;
case MotionEvent.ACTION_CANCEL:
break;
default:
break;
}
return true;
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
}
You are not initializing path. Most likely, your program is crashing with a NullPointerException. Try adding this inside the CustomView constructor:
path = new Path();
In the future, when you are posting about your Android program crashing, it would be most helpful if you posted the logcat output from a crash.
I have a problem with my activity which showing CUBE 3D (simple OpenGL example). When I pressing back key on my phone or emulator, it should return to main menu, but instead of returning nothing happens. Any clue?
Here's the code:
public class Graphic3D extends Activity {
private GLSurfaceView glView; // Use subclass of GLSurfaceView (NEW)
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Allocate a custom subclass of GLSurfaceView (NEW)
glView = new MyGLSurfaceView(this);
setContentView(glView); // Set View (NEW)
}
#Override
public void onBackPressed() {
super.onBackPressed();
// ????????
}
#Override
protected void onPause() {
super.onPause();
glView.onPause();
}
#Override
protected void onResume() {
super.onResume();
glView.onResume();
}
}
MySurfaceView class:
public class MyGLSurfaceView extends GLSurfaceView {
Graphics3DRenderer renderer; // Custom GL Renderer
// For touch event
private final float TOUCH_SCALE_FACTOR = 180.0f / 320.0f;
private float previousX;
private float previousY;
// Constructor - Allocate and set the renderer
public MyGLSurfaceView(Context context) {
super(context);
renderer = new Graphics3DRenderer(context);
this.setRenderer(renderer);
// Request focus, otherwise key/button won't react
this.requestFocus();
this.setFocusableInTouchMode(true);
}
// Handler for key event
#Override
public boolean onKeyDown(int keyCode, KeyEvent evt) {
switch(keyCode) {
case KeyEvent.KEYCODE_DPAD_LEFT: // Decrease Y-rotational speed
renderer.speedY -= 0.3f;
break;
case KeyEvent.KEYCODE_DPAD_RIGHT: // Increase Y-rotational speed
renderer.speedY += 0.3f;
break;
case KeyEvent.KEYCODE_DPAD_UP: // Decrease X-rotational speed
renderer.speedX -= 0.3f;
break;
case KeyEvent.KEYCODE_DPAD_DOWN: // Increase X-rotational speed
renderer.speedX += 0.3f;
break;
case KeyEvent.KEYCODE_VOLUME_DOWN:// Zoom out (decrease z)
renderer.z -= 0.4f;
break;
case KeyEvent.KEYCODE_VOLUME_UP: // Zoom in (increase z)
renderer.z += 0.4f;
break;
case KeyEvent.KEYCODE_DPAD_CENTER:
renderer.speedY = 0;
renderer.speedX = 0;
renderer.z = -6.0f;
break;
}
return true; // Event handled
}
// Handler for touch event
#Override
public boolean onTouchEvent(final MotionEvent evt) {
float currentX = evt.getX();
float currentY = evt.getY();
float deltaX, deltaY;
switch (evt.getAction()) {
case MotionEvent.ACTION_MOVE:
// Modify rotational angles according to movement
deltaX = currentX - previousX;
deltaY = currentY - previousY;
renderer.angleX += deltaY * TOUCH_SCALE_FACTOR;
renderer.angleY += deltaX * TOUCH_SCALE_FACTOR;
}
// Save current x, y
previousX = currentX;
previousY = currentY;
return true; // Event handled
}
}
In an Activity, calling finish() will close the current Activity. If you haven't closed the main menu Activity, it should "open" itself.
If you need to start an Activity again, for example if your menu Activity is closed, you can do the following.
Intent i = new Intent(getApplicationContext(), Menu.class);
startActivity(i);
finish();