以编程方式更改导航抽屉的边距

Question

我有一个导航抽屉，但我想设置一些边距，就像在XML文件中设置android:layout_marginTop="72dp"一样，但我想以编程方式设置它们。

我activity_main.xml中：

<FrameLayout 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    android:fitsSystemWindows="false" 
    android:background="@drawable/back_blue_translucent" 
    xmlns:android="http://schemas.android.com/apk/res/android"> 

    <android.support.v4.widget.DrawerLayout 
     xmlns:android="http://schemas.android.com/apk/res/android" 
     xmlns:tools="http://schemas.android.com/tools" 
     android:id="@+id/drawer_layout" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     android:fitsSystemWindows="false" 
     tools:context="com.bentleycarr.mentalmaths.MainActivity"> 

     <FrameLayout 
      android:id="@+id/container" 
      android:layout_width="match_parent" 
      android:layout_height="match_parent" 
      android:background="#f9f9f9"/> 

     <fragment android:id="@+id/navigation_drawer" 
      android:layout_width="@dimen/navigation_drawer_width" 
      android:layout_height="match_parent" 
      android:layout_gravity="start" 
      android:layout_marginTop="72dp" <!--I want to change this --> 
      android:name="com.bentleycarr.mentalmaths.NavigationDrawerFragment" /> 

    </android.support.v4.widget.DrawerLayout> 
</FrameLayout> 

以上，它说：android:layout_marginTop="72dp" - 我要改变“那个”在MainActivity.java另一个号码，但我只能找到关于如何做到这一点的信息LinearLayout或RelativeLayout等，而不是<fragment android:id="@+id/navigation_drawer"任何帮助/建议将不胜感激。

我试过Aashir的回答，但它坠毁了。这里的日志： （忽略这个现在 - 我可能添加了错误的ID）。

Process: com.bentleycarr.mentalmaths, PID: 23729 
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.bentleycarr.mentalmaths/com.bentleycarr.mentalmaths.MainActivity}: java.lang.ClassCastException: android.support.v4.widget.DrawerLayout$LayoutParams cannot be cast to android.widget.FrameLayout$LayoutParams 
     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195) 
     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245) 
     at android.app.ActivityThread.access$800(ActivityThread.java:135) 
     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196) 
     at android.os.Handler.dispatchMessage(Handler.java:102) 
     at android.os.Looper.loop(Looper.java:136) 
     at android.app.ActivityThread.main(ActivityThread.java:5017) 
     at java.lang.reflect.Method.invokeNative(Native Method) 
     at java.lang.reflect.Method.invoke(Method.java:515) 
     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779) 
     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595) 
     at dalvik.system.NativeStart.main(Native Method) 
Caused by: java.lang.ClassCastException: android.support.v4.widget.DrawerLayout$LayoutParams cannot be cast to android.widget.FrameLayout$LayoutParams 
     at com.bentleycarr.mentalmaths.MainActivity.onCreate(MainActivity.java:55) 
     at android.app.Activity.performCreate(Activity.java:5231) 
     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087) 
     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159) 
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245) 
            at android.app.ActivityThread.access$800(ActivityThread.java:135) 
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196) 
            at android.os.Handler.dispatchMessage(Handler.java:102) 
            at android.os.Looper.loop(Looper.java:136) 
            at android.app.ActivityThread.main(ActivityThread.java:5017) 
            at java.lang.reflect.Method.invokeNative(Native Method) 
            at java.lang.reflect.Method.invoke(Method.java:515) 
            at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779) 
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595) 

Answer 1

尝试：

FrameLayout root = (FrameLayout) findViewById(R.id.yourID); 
FrameLayout.LayoutParams params = (FrameLayout.LayoutParams)root.getLayoutParams(); 
    params.setMargins(left, top, right, bottom); 
    root.setLayoutParams(params); 

Answer 2

我有一个任务来设置保证金从屏幕边框的确切大小（左/右），所以我overrided默认generateLayoutParams(attrs)在抽屉布局，以调整其视：

public class CustomMarginDrawerLayout extends DrawerLayout { 
    private static final int DRAWER_MARGIN_IN_DP = 48; 
    private final Context context; 

    public CustomMarginDrawerLayout(Context context) { 
     super(context); 
     this.context = context; 
    } 

    public CustomMarginDrawerLayout(Context context, AttributeSet attrs) { 
     super(context, attrs); 
     this.context = context; 
    } 

    public CustomMarginDrawerLayout(Context context, AttributeSet attrs, int defStyle) { 
     super(context, attrs, defStyle); 
     this.context = context; 
    } 

    @Override 
    public ViewGroup.LayoutParams generateLayoutParams(AttributeSet attrs) { 
     ViewGroup.LayoutParams params = super.generateLayoutParams(attrs); 
     int margin = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, DRAWER_MARGIN_IN_DP, getResources().getDisplayMetrics()); 
     params.width = getScreenWidth(context) - margin; 
     return params; 
    } 

    private int getScreenWidth(Context context) { 
     WindowManager windowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE); 
     DisplayMetrics metrics = new DisplayMetrics(); 
     windowManager.getDefaultDisplay().getMetrics(metrics); 
     return metrics.widthPixels; 
    } 
}