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Java 以编程方式添加视图忽略填充_Java_Android - Fatal编程技术网

Java 以编程方式添加视图忽略填充

Java 以编程方式添加视图忽略填充,java,android,Java,Android,我正在向我的相对布局添加一个视图,四周都有16dp填充 View blackView = new View(RestaurantActivity.this); blackView.setMinimumHeight(height); blackView.setMinimumWidth(width); blackView.setBackgroundColor(Color.BLACK

我正在向我的相对布局添加一个视图,四周都有16dp填充

View blackView = new View(RestaurantActivity.this);
                    blackView.setMinimumHeight(height);
                    blackView.setMinimumWidth(width);
                    blackView.setBackgroundColor(Color.BLACK);
                    blackView.setAlpha(0.5f);
                    rl.addView(blackView);
这个视图也有填充,但我想让它填满整个屏幕,忽略填充,怎么能通过编程实现呢

谢谢

编辑

我试过这个

ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams)blackView.getLayoutParams();
                    float scale = getResources().getDisplayMetrics().density;
                    int dpAsPixels = (int) (-16*scale + 0.5f);
                    params.rightMargin = dpAsPixels;
                    params.leftMargin = dpAsPixels;
                    params.bottomMargin = dpAsPixels;
                    blackView.setLayoutParams(params);
但我犯了这个错误

 E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.NullPointerException
        at com.james.duss.ResturantActivity$1.onClick(ResturantActivity.java:156)
        at android.view.View.performClick(View.java:4204)
        at android.view.View$PerformClick.run(View.java:17355)
        at android.os.Handler.handleCallback(Handler.java:725)
        at android.os.Handler.dispatchMessage(Handler.java:92)
        at android.os.Looper.loop(Looper.java:137)
        at android.app.ActivityThread.main(ActivityThread.java:5041)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:511)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
        at dalvik.system.NativeStart.main(Native Method)
工作代码:

    ViewGroup.MarginLayoutParams params = (ViewGroup.MarginLayoutParams)blackView.getLayoutParams();
    float scale = getResources().getDisplayMetrics().density;
    int dpAsPixels = (int) (-16*scale + 0.5f);
    params.rightMargin = dpAsPixels;
    params.leftMargin = dpAsPixels;
    params.bottomMargin = dpAsPixels;
    blackView.setLayoutParams(params);

在xml布局文件中的
RelativeLayout
android:cliptoppadding=“false”

下面是一个更好、更干净的解决方案,可以在dp中获得填充,而不是像素

您必须将填充存储在资源文件(即
dimens.xml
)中,因此您只需调用:

int padding = getResources().getDimensionPixelOffset(R.dimen.padding);
它为您进行转换。然后可以将填充设置为所需的视图,例如:

mPicImageView.setPadding(padding, padding, padding, padding);

好的,但我想保留此活动中其他视图的填充,然后尝试设置负填充。转换16dp it px。我需要设置负边距,但不确定如何设置?请参阅editPost full Logcaterror@dieter_h请参见
resturantivity.java
第156行
onClick
event中的additionNull指针您的问题是关于填充忽略,但您的问题是NullPointerException?你的问题到底是什么?