How to bring view on front of everything?

问题:

I have activity and a lot of widgets on it, some of them have animations and because of the animations some of the widgets are moving (translating) one over another. For example the text view is moving over some buttons . . .

Now the thing is I want the buttons to be always on the front. And when the textview is moving I want to move behind the buttons.

I can not achieve this I tried everything I know, and "bringToFront()" definitelly doesn't work.

note I do not want to control the z-order by the order of placing element to layout cause I simply can't :), the layout is complex and I can not place all the buttons at the begging of the layout

回答1:

You can call bringToFront() on the view you want to get in the front

This is an example:

    yourView.bringToFront();

回答2:

I've been looking through stack overflow to find a good answer and when i couldn't find one i went looking through the docs.

no one seems to have stumbled on this simple answer yet:

ViewCompat.setTranslationZ(view, translationZ);

default translation z is 0.0

回答3:

bringToFront() is the right way, but, NOTE that you must call bringToFront() and invalidate() method on highest-level view (under your root view), for e.g.:

Your view's hierarchy is:

-RelativeLayout
|--LinearLayout1
|------Button1
|------Button2
|------Button3
|--ImageView
|--LinearLayout2
|------Button4
|------Button5
|------Button6

So, when you animate back your buttons (1->6), your buttons will under (below) the ImageView. To bring it over (above) the ImageView you must call bringToFront() and invalidate() method on your LinearLayouts. Then it will work :) **NOTE: Remember to set android:clipChildren="false" for your root layout or animate-view's gradparent_layout. Let's take a look at my real code:

.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:hw="http://schemas.android.com/apk/res-auto"
    android:id="@+id/layout_parent"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/common_theme_color"
    android:orientation="vertical" >

    <com.binh.helloworld.customviews.HWActionBar
        android:id="@+id/action_bar"
        android:layout_width="match_parent"
        android:layout_height="@dimen/dimen_actionbar_height"
        android:layout_alignParentTop="true"
        hw:titleText="@string/app_name" >
    </com.binh.helloworld.customviews.HWActionBar>

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@id/action_bar"
        android:clipChildren="false" >

        <LinearLayout
            android:id="@+id/layout_top"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentTop="true"
            android:gravity="center_horizontal"
            android:orientation="horizontal" >
        </LinearLayout>

        <ImageView
            android:id="@+id/imgv_main"
            android:layout_width="@dimen/common_imgv_height"
            android:layout_height="@dimen/common_imgv_height"
            android:layout_centerInParent="true"
            android:contentDescription="@string/app_name"
            android:src="@drawable/ic_launcher" />

        <LinearLayout
            android:id="@+id/layout_bottom"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:gravity="center_horizontal"
            android:orientation="horizontal" >
        </LinearLayout>
    </RelativeLayout>

</RelativeLayout>

Some code in .java

private LinearLayout layoutTop, layoutBottom;
...
layoutTop = (LinearLayout) rootView.findViewById(R.id.layout_top);
layoutBottom = (LinearLayout) rootView.findViewById(R.id.layout_bottom);
...
//when animate back
//dragedView is my layoutTop's child view (i added programmatically) (like buttons in above example) 
dragedView.setVisibility(View.GONE);
layoutTop.bringToFront();
layoutTop.invalidate();
dragedView.startAnimation(animation); // TranslateAnimation
dragedView.setVisibility(View.VISIBLE);

GLuck!

回答4:

Try FrameLayout, it gives you the possibility to put views one above another. You can create two LinearLayouts: one with the background views, and one with foreground views, and combine them using the FrameLayout. Hope this helps.

回答5:

An even simpler solution is to edit the XML of the activity. Use

android:translationZ=""

回答6:

There can be another way which saves the day. Just init a new Dialog with desired layout and just show it. I need it for showing a loadingView over a DialogFragment and this was the only way I succeed.

Dialog topDialog = new Dialog(this, android.R.style.Theme_Translucent_NoTitleBar);
topDialog.setContentView(R.layout.dialog_top);
topDialog.show();

bringToFront() might not work in some cases like mine. But content of dialog_top layout must override anything on the ui layer. But anyway, this is an ugly workaround.

回答7:

i have faced the same problem. the following solution have worked for me.

 FrameLayout glFrame=(FrameLayout) findViewById(R.id.animatedView);
        glFrame.addView(yourView);
        glFrame.bringToFront();
        glFrame.invalidate();

回答8:

You can try to use the bringChildToFront, you can check if this documentation is helpful in the Android Developers page.

回答9:

You need to use framelayout. And the better way to do this is to make the view invisible when thay are not require. Also you need to set the position for each and every view,So that they will move according to there corresponding position

回答10:

If you are using a LinearLayout you should call myView.bringToFront() and after you should call parentView.requestLayout() and parentView.invalidate() to force the parent to redraw with the new child order.

回答11:

If you are using ConstraintLayout, just put the element after the other elements to make it on front than the others

回答12:

You can set visibility to false of other views.

view1.setVisibility(View.GONE);
view2.setVisibility(View.GONE);
...

or

view1.setVisibility(View.INVISIBLE);
view2.setVisibility(View.INVISIBLE);
...

and set

viewN.setVisibility(View.VISIBLE);