问题
I\'ve been scouring the interwebs (e.g. Android documentation, answers here, etc.) for the answer to what I thought would be a fairly trivial question. How do you achieve a translucent action bar like the ones in Google Music and YouTube (links are image examples)?
I want video content to be full screen and not constrained/pushed down by the action bar while still leveraging the benefits of a built in UI component. I can obviously use a completely custom view, but I\'d rather leverage the ActionBar if possible.
Manifest
<activity
android:name=\"videoplayer\"
android:theme=\"@android:style/Theme.Holo\"
android:launchMode=\"singleTop\"
android:configChanges=\"keyboardHidden|orientation\"/>
Activity
// Setup action bar
ActionBar actionBar = getActionBar();
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_STANDARD);
View customActionBarView = getLayoutInflater().inflate(R.layout.player_custom_action_bar, null);
actionBar.setCustomView(customActionBarView,
new ActionBar.LayoutParams(ActionBar.LayoutParams.MATCH_PARENT,
R.dimen.action_bar_height));
actionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
Menu
<menu xmlns:android=\"http://schemas.android.com/apk/res/android\">
<item
android:id=\"@+id/button1\"
android:icon=\"@drawable/button1\"
android:showAsAction=\"always\"/>
<item
android:id=\"@+id/button2\"
android:icon=\"@drawable/button2\"
android:showAsAction=\"always\"/>
</menu>
Custom ActionBar View
<LinearLayout
xmlns:android=\"http://schemas.android.com/apk/res/android\"
android:id=\"@+id/custom_action_bar\"
android:layout_width=\"match_parent\"
android:layout_height=\"wrap_content\"
android:orientation=\"horizontal\"
android:gravity=\"center\"
android:background=\"@color/TranslucentBlack\">
<!--Home icon with arrow-->
<ImageView
android:id=\"@+id/home\"
android:src=\"@drawable/home\"
android:layout_width=\"wrap_content\"
android:layout_height=\"match_parent\"/>
<!--Another image-->
<ImageView
android:id=\"@+id/image\"
android:layout_width=\"wrap_content\"
android:layout_height=\"match_parent\"
android:visibility=\"visible\"/>
<!--Text if no image-->
<TextView
android:id=\"@+id/text\"
android:layout_width=\"wrap_content\"
android:layout_height=\"match_parent\"
android:gravity=\"center_vertical\"
android:visibility=\"gone\"/>
<!--Title-->
<TextView
android:id=\"@+id/title\"
android:layout_width=\"wrap_content\"
android:layout_height=\"match_parent\"
android:paddingLeft=\"20dp\"
android:gravity=\"center_vertical\"/>
</LinearLayout>
回答1:
If you want your activity to be fullscreen but still show an actionbar, but with an alpha you have to request overlaymode for the actionbar in onCreate() of your activity:
getWindow().requestFeature(Window.FEATURE_ACTION_BAR_OVERLAY);
//getWindow().requestFeature(WindowCompat.FEATURE_ACTION_BAR_OVERLAY); << Use this for API 7+ (v7 support library)
Then after you call setContentView(..) (since setContentView(..) also initializes the actionbar next to setting the content) you can set a background drawable on your actionbar:
getActionBar().setBackgroundDrawable(getResources().getDrawable(R.drawable.actionbar_bg));
which can be a shape drawable with an alpha put in res/drawable:
<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle">
<solid android:color="#BB000000" />
</shape>
You could also do this completely programatically by creating a ColorDrawable:
getActionBar().setBackgroundDrawable(new ColorDrawable(Color.argb(128, 0, 0, 0)));
Otherwise ofcourse you can hide the actionbar completely; in that case you can set a custom theme on your activity in your manifest:
@android:style/Theme.NoTitleBar.Fullscreen
or programmatically by calling
getActionBar().hide();
回答2:
In addition to the correct answer, if you are using AppcomatActivity, call supportRequestWindowFeature instead of
Old Version:
getWindow().requestFeature(Window.FEATURE_ACTION_BAR_OVERLAY);
You want to use:
@Override
protected void onCreate(Bundle savedInstanceState) {
supportRequestWindowFeature(Window.FEATURE_ACTION_BAR_OVERLAY);
super.onCreate(savedInstanceState);
}
回答3:
I think you should be able to do this using the Window flag FEATURE_ACTION_BAR_OVERLAY.
Before you call setContentView() in your activity,
Call:
getWindow().requestFeature(Window.FEATURE_ACTION_BAR_OVERLAY);
And it will use an overlaid ActionBar instead of pushing down your window.
回答4:
The above code is absolutely correct for making an action bar.
Instead of
getActionBar().setBackgroundDrawable(new ColorDrawable(Color.argb(128, 0, 0, 0)))
use
getActionBar().setBackgroundDrawable(new ColorDrawable(Color.TRANSPARENT));
In this way, you will able to see the action bar fully transparent.
回答5:
Here is how I got this to work:
1) Request for actionbar overlay programmatically by calling
getWindow().requestFeature(Window.FEATURE_ACTION_BAR_OVERLAY);
this 'requestFeature()' must be requested from your activity 'onCreate()' method before calling for 'setContentView(R.layout.my_layout)':
2) set the actionbar color by calling setBackgroundDrawable() like so:
getSupportActionBar().setBackgroundDrawable(new ColorDrawable(Color.parseColor("#00212121")) );
this method requires either a reference to a drawable or you can also use a color parser to parse a hex color value (first 2 digits are used for alpha channel starting at #00 to #FF)
Note that I am using actionBarSherlok getSupportActionBar() but this should work with any action bar.
If you still cant get this to work, try adding this to your theme style
<item name="windowActionBarOverlay">true</item>
<item name="android:actionBarStyle">@style/ActionBar.Transparent.Example</item>
<item name="android:windowActionBarOverlay">true</item>
回答6:
I just like to share with you the steps I took to achieve this:
1) At the OnCreate of your activity,
getWindow().requestFeature(Window.FEATURE_ACTION_BAR_OVERLAY);
then
getWindow().setFlags(WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION,
WindowManager.LayoutParams.FLAG_TRANSLUCENT_NAVIGATION);
This is done before setContentView.
2) After setContentView, you can do the following
getSupportActionBar().setBackgroundDrawable(new ColorDrawable(Color.argb(0, 100, 181, 246)));
Where the alpha value of 0 means it is fully transparent.
来源：https://stackoverflow.com/questions/6749261/custom-translucent-android-actionbar