android - 如何通过代码修改marginTop？

我正试图找到一种方法，通过代码修改EditText的marginTop…我读到了setLayoutParams，但我得到了forceClose，并收到了以下消息：

08-05 14:53:59.715: ERROR/AndroidRuntime(913): java.lang.ClassCastException: android.widget.LinearLayout$LayoutParams
08-05 14:53:59.715: ERROR/AndroidRuntime(913):     at android.widget.RelativeLayout$DependencyGraph.findRoots(RelativeLayout.java:1291)
08-05 14:53:59.715: ERROR/AndroidRuntime(913):     at android.widget.RelativeLayout$DependencyGraph.getSortedViews(RelativeLayout.java:1238)
08-05 14:53:59.715: ERROR/AndroidRuntime(913):     at android.widget.RelativeLayout.sortChildren(RelativeLayout.java:279)
08-05 14:53:59.715: ERROR/AndroidRuntime(913):     at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:299)
08-05 14:53:59.715: ERROR/AndroidRuntime(913):     at android.view.View.measure(View.java:7964)

有人能解释一下我该怎么做吗？

giveuser = (EditText) findViewById(R.id.txt_username);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT);
        lp.setMargins(5,5,5,5);
        giveuser.setLayoutParams(lp);

在XML中：

<EditText android:id="@+id/txt_username"
        android:layout_height="wrap_content" android:layout_width="350px"
        android:layout_centerHorizontal="true" android:layout_below="@+id/loginsubtitle"
        android:layout_marginTop="180dip" android:singleLine="true"
        android:hint="Identifiant" />

最佳答案

试试这个：

LayoutParams params = EditTextName.getLayoutParams();
params.setMargins(left, top, right, bottom);
EditTextName.setLayoutParams(params);