#layoutparams

How to: How to programmatically set the layout_align_parent_right attribute of a Button in Relative Layout?

How to programmatically set the layout_align_parent_right attribute of a Button in Relative Layout?

HI! I have a relative layout which I am creating programmatically:

RelativeLayout layout = new RelativeLayout( this ); RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT);

Now I have two buttons which I want to add in this…

相信應該有些開發者，希望在程式裡取得View的margin設定值

但是View有getPadding的相關函式，但沒有取得margin的相關函式

這時會要取得view的LayoutParams，但是一個不小心就會產生

ClassCastException，這時要注意目前的View的父層Layout是哪一類型

如果你的Layout配置如下：

<ListView android:id="@+id/list" android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_weight="1.0" android:layout_margin="4dp" /> <Button android:layout_width="fill_parent" android:layout_height="wrap_content" android:text="@string/linear_layout_9_button" /> </LinearLayout>

如果你想取得id為list的margin設定值時，因為其父層Layout為LinearLayout，所以要取得其margin時，程式碼要這樣子寫才不會有exception

ListView list = (ListView)findViewById(R.id.list); LinearLayout.LayoutParams lp = (LinearLayout.LayoutParams)list.getLayoutParams(); int marginLeft = lp.leftMargin;