With version 23.2 we can now use WRAP_CONTENT for recyclerView height, which is great. I am doing this, however I want to recalculate the height after an item is added (or removed) to the adapter (thus increasing or decreasing the height).
My particular RecyclerView is starting with 1 item, and then adding items as the user makes selection. So I need the RecyclerView layout to increase in height, up to a point. Ideally this would happen with a smooth animation when the list increases or decreases.
How can we make it WRAP_CONTENT after it has been laid out?
Tried:
recyclerview.requestLayout();
recyclerview.invalidate();
I would expect it to work with View.invalidate().
If that does not work, try to call either requestLayout or invalidate on the parent view.
How RecyclerView Resize itself based on with the new LayoutManger
The RecyclerView widget provides an advanced and flexible base for creating lists and grids as well as supporting animations. This release brings an exciting new feature to the LayoutManager API: auto-measurement! This allows a RecyclerView to size itself based on the size of its contents. This means that previously unavailable scenarios, such as using WRAP_CONTENT for a dimension of the RecyclerView, are now possible. You’ll find all built in LayoutManagers now support auto-measurement.
Due to this change, make sure to double check the layout parameters of your item views: previously ignored layout parameters (such as MATCH_PARENT in the scroll direction) will now be fully respected.
If you have a custom LayoutManager that does not extend one of the built in LayoutManagers, this is an opt-in API - you’ll be required to call setAutoMeasureEnabled(true) as well as make some minor changes as detailed in the Javadoc of the method.
Note that although RecyclerView animates its children, it does not animate its own bounds changes. If you would like to animate the RecyclerView bounds as they change, you can use the Transition APIs.
Please read this
Option I
Did you see this answer?
It's not using the recyclerView's WRAP_CONTENT, but it might work.
You can also create your own custom recyclerView (extends RecyclerView) and override the onMeasure() method there instead using the layoutManager in the link.
Option II
Try to set the layout params before drawing the view. I haven't checked if it is called when recyclerView layout changes, but if it does, then it will work. Something like this (in your Activity/Fragment onCreate()/onCreateView() method:
recyclerView.getViewTreeObserver().addOnPreDrawListener(new ViewTreeObserver.OnPreDrawListener() {
#Override
public boolean onPreDraw() {
recyclerView.getViewTreeObserver().removeOnPreDrawListener(this);
YourParentLayoutType.LayoutParams params = (YourParentLayoutType.LayoutParams) recyclerView.getLayoutParams();
params.height = YourParentLayoutType.LayoutParams.WRAP_CONTENT;
recyclerView.setLayoutParams(params);
return true;
}
});
Use your recyclerView's parent layout type instead of YourParentLayoutType in the code.
I'm not sure this will work when layout refreshes, but maybe worth a try.
Use this class:
Please use 23.2.1 as 23.2 was way buggy.
Also have you tried to call notifyDataSetChanged on the recyclerview adapter , as far as i think it should expand without problem if you have given wrap_content as height of recyclerview
else u can use this class:
import android.content.Context;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;
import android.view.ViewGroup;
public class MyLinearLayoutManager extends LinearLayoutManager {
public MyLinearLayoutManager(Context context, int orientation, boolean reverseLayout) {
super(context, orientation, reverseLayout);
}
private int[] mMeasuredDimension = new int[2];
#Override
public void onMeasure(RecyclerView.Recycler recycler, RecyclerView.State state,
int widthSpec, int heightSpec) {
final int widthMode = View.MeasureSpec.getMode(widthSpec);
final int heightMode = View.MeasureSpec.getMode(heightSpec);
final int widthSize = View.MeasureSpec.getSize(widthSpec);
final int heightSize = View.MeasureSpec.getSize(heightSpec);
int width = 0;
int height = 0;
for (int i = 0; i < getItemCount(); i++) {
if (getOrientation() == HORIZONTAL) {
measureScrapChild(recycler, i,
View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED),
heightSpec,
mMeasuredDimension);
width = width + mMeasuredDimension[0];
if (i == 0) {
height = mMeasuredDimension[1];
}
} else {
measureScrapChild(recycler, i,
widthSpec,
View.MeasureSpec.makeMeasureSpec(0, View.MeasureSpec.UNSPECIFIED),
mMeasuredDimension);
height = height + mMeasuredDimension[1];
if (i == 0) {
width = mMeasuredDimension[0];
}
}
}
switch (widthMode) {
case View.MeasureSpec.EXACTLY:
width = widthSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}
switch (heightMode) {
case View.MeasureSpec.EXACTLY:
height = heightSize;
case View.MeasureSpec.AT_MOST:
case View.MeasureSpec.UNSPECIFIED:
}
int widthDesired = Math.min(widthSize,width);
setMeasuredDimension(widthDesired, height);
}
private void measureScrapChild(RecyclerView.Recycler recycler, int position, int widthSpec,
int heightSpec, int[] measuredDimension) {
View view = recycler.getViewForPosition(position);
// For adding Item Decor Insets to view
super.measureChildWithMargins(view, 0, 0);
RecyclerView.LayoutParams p = (RecyclerView.LayoutParams) view.getLayoutParams();
int childWidthSpec = ViewGroup.getChildMeasureSpec(
widthSpec,
getPaddingLeft() + getPaddingRight() + getDecoratedLeft(view) + getDecoratedRight(view),
p.width);
int childHeightSpec = ViewGroup.getChildMeasureSpec(
heightSpec,
getPaddingTop() + getPaddingBottom() + getDecoratedTop(view) + getDecoratedBottom(view) ,
p.height);
view.measure(childWidthSpec, childHeightSpec);
// Get decorated measurements
measuredDimension[0] = getDecoratedMeasuredWidth(view) + p.leftMargin + p.rightMargin;
measuredDimension[1] = getDecoratedMeasuredHeight(view) + p.bottomMargin + p.topMargin;
recycler.recycleView(view);
}
}
Related
I am a bit new to android, but I know java fairly well.
As a simple means of scalability, i use these simple functions:
public void scaleMyView(float s) {
scaleFactor = scaleFactor + s;
// s will usually be like 0.1 or -0.1 = 10% size gain/loss
View myMainView = findViewById(R.id.MyMainView);
Display display = getWindowManager().getDefaultDisplay();
Point size = new Point();
display.getSize(size);
int x = size.x;
int y = size.y;
myMainView.setScaleX(scaleFactor);
myMainView.setScaleY(scaleFactor);
myMainView.layout(0, 0, ((int)(x/scaleFactor)), ((int)(y/scaleFactor)))
myMainView.setPivotX(0);
myMainView.setPivotY(getActionBar().getHeight());
}
Which does exactly what I want, changing the main view and all within it in size and keeping it in place.
Now comes the problem:
Whenever I add a fragment to a sub-view of that main-view, the "layout" part is reset, and though scale and position remain, size shrinks back to default.
(The fragments are very simple, basically simple buttons.)
I tried quite a few things, and I still have no idea where or how to fix that.
Any help is highly appreciated!
Try to use "addOnLayoutChangeListener" method on your mainView:
myMainView.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
#Override
public void onLayoutChange(
View view, int i, int i2, int i3, int i4, int i5, int i6, int i7, int i8)
{
// set view properties here
}
});
myMainView.requestLayout();
I have an android dialog which i want to position in a specific position in its window.
I'm using API 8
how come int a == -2 and int b == 153 are not positive?
what is the difference between
getLayoutParams().height;
mToolTipLayout.getHeight();
I have the following code
public void initViews(int orientation) {
mToolTipLayout = ((LinearLayout) findViewById(R.id.tooltip_layout));
ViewTreeObserver vto = mToolTipLayout.getViewTreeObserver();
vto.addOnGlobalLayoutListener(new OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
mToolTipLayout.getViewTreeObserver().removeGlobalOnLayoutListener(this);
setPosition();
}
});
private void setPosition() {
int a = mToolTipLayout.getLayoutParams().height;
int b = mToolTipLayout.getHeight();
}
Layout params specify how the measure and layout process should work. They are not updated in the measure/layout process. -2 is the value for WRAP_CONTENT.
The measures themselves are available in the views themselves, not their layout params. 153 is the measured pixel height in your case, measured with WRAP_CONTENT spec.
Yes, -2 means WRAP_CONTENT. To get a height of a layout in this case you cannot use getLayoutParams().height or getHeight() (-2 and 0 respectively). You should get a height of inner view (for instance, with view.getLayoutParams().height). Probably add paddings.
I'm developing an android app which requires an imageview (and textviews) to be updated on button click, but I want the image to match the height of four of my textviews. When I set the height of the imageview, it seems to keep the height of the previous update, not the current one. Here is my code to update the image and its height.
int nameHeight = t_name.getHeight();
int timeHeight = r_time.getHeight();
int dateHeight = r_date.getHeight();
int locaHeight = r_loca.getHeight();
int totalHeight = nameHeight + timeHeight + dateHeight + locaHeight;
i_img.getLayoutParams().height = totalHeight;
Bitmap image = getBitmapFromURL(event_image.get(eventToUse));
i_img.setImageBitmap(image);
After touching the layout params, call requestLayout() to have the changes take effect.
I am currently working on custom animation between switching pages in ViewPager. When I slide to the left, View is moving to the left and from below of it new View is coming to the front. I would like to make the view, that moves to the left (that I dispose) to shrink like on the folowing images:
On the second and third image I didn't picture new View coming to the front, but I think it wasn't necessary. Do you have any idea how can I modify the code? I would like to change height of TableLayout, RelativeLayout and FrameLayout and keep the height of both TextViews. Also I would have to change X-position of the whole View. I am looking forward for your creative answers (code). Below I attach my code for the animation.
import android.view.View;
import android.widget.RelativeLayout;
import android.annotation.SuppressLint;
import android.support.v4.view.ViewPager.PageTransformer;
public class DepthPageTransformer implements PageTransformer {
private static float MIN_SCALE = 0.75f;
#SuppressLint("NewApi")
public void transformPage(View view, float position) {
int pageWidth = view.getWidth();
if (position < -1) { // [-Infinity,-1)
// This page is way off-screen to the left.
view.setAlpha(0);
} else if (position <= 0) { // [-1,0]
// Use the default slide transition when moving to the left page
view.setTranslationX(0);
view.setScaleX(1);
view.setScaleY(1);
//float scaleFactor = (1 - Math.abs(position));
//WHAT TO PUT HERE TO ARCHIVE MY GOAL??
//This is how I can get particular layouts:
// RelativeLayout relativeLayout = (RelativeLayout) view.findViewById(R.id.fragment_object_canvas_RelativeLayout1);
//relativeLayout.setScaleX(scaleFactor);
//relativeLayout.setScaleY(scaleFactor);
} else if (position <= 1) { // (0,1]
// Fade the page out.
view.setAlpha(1 - position);
// Counteract the default slide transition
view.setTranslationX(pageWidth * -position);
//view.setRotation(1 - (position*360));
// Scale the page down (between MIN_SCALE and 1)
float scaleFactor = MIN_SCALE
+ (1 - MIN_SCALE) * (1 - Math.abs(position));
view.setScaleX(scaleFactor);
view.setScaleY(scaleFactor);
} else { // (1,+Infinity]
// This page is way off-screen to the right.
view.setAlpha(0);
}
}
}
UPDATE:
I can manipulate with height of whole View (for now I can do only this) with the following code:
LinearLayout relativeLayout = (LinearLayout) view.findViewById(R.id.fragment_object_canvas_linearLayout1);
relativeLayout.setLayoutParams(new FrameLayout.LayoutParams(relativeLayout.getWidth(), NEW_HEIGHT_HERE)));
However, I am not sure what should I put into NEW_HEIGHT_HERE variable to make it work corectly...
try to work with a position float variable.
Get the height of your layout and...:
relativeLayout.setLayoutParams(....,position*height+height)
You seem pretty insistent on people posting original code, but why reinvent the wheel? This library has a ton of great animations for a ViewPager, including one very similar to what you seem to be requesting.
https://github.com/jfeinstein10/JazzyViewPager
JazzyViewPager -
An easy to use ViewPager that adds an awesome set of custom swiping animations. Just change your ViewPagers to JazzyViewPagers and you're good to go!
public enum TransitionEffect {
Standard,
Tablet,
CubeIn,
CubeOut,
Flip,
Stack,
ZoomIn,
ZoomOut,
RotateUp,
RotateDown,
Accordion
}
You can select your animation by calling
private JazzyViewPager mJazzy;
/* ... */
mJazzy.setTransitionEffect(TransitionEffect.*);
I want to measure the height of each item in a ListView before the rendering.
I added this method to my custom ListView
public void measureItemsHeight() {
mItemCount = getAdapter().getCount();
if(mItemOffsetY == null){
mItemOffsetY = new int[mItemCount];
}
for(int i = 0; i < mItemCount; ++i){
View view = getAdapter().getView(i, null, this);
view.measure(0, 0);
mItemHeight[i] = view.getMeasuredHeight();
}
}
Then, inside my activity's onCreate():
mListView.getViewTreeObserver().addOnGlobalLayoutListener(
new ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
mListView.measureItemsHeight();
}
}
);
The values i get are different than the ones reported by getHeight(), eg getMeasuredHeight() returns 48, and the getHeight() returns 72.
The layout i use for the items is the simple_list_item
It looks to me this like a hdpi and xhdpi problem, is there a way to fix this? The device I use to debug is the Samsung SGS2, maybe that is the problem.
I would suggest you to use custom list,Make separate layout for list row.Assign following property to that views layout:android:layout_height=wrap_content. Thats it.Good Luck!