TextView setGravity（）在java中不起作用

Question

I'm stuck on a problem and I don't know, what causes it. I have a very simple Layout like this:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
    android:id="@+id/my_text_view"
    android:layout_width="wrap_content"
    android:layout_height="fill_parent"
    android:layout_gravity="NOTE_THIS"
    android:textColor="#FFFFFF"
    android:textSize="22dp"
    android:text="TestText"/>
</LinearLayout>

which is included inside another layout. If I change the gravity inside the xml I see same Result in Layout-Editor and on my phone. If I wanna apply the Gravity programatically like with myTextView.setGravity(Gravity.CENTER) it doesn't Change anything. And I cannot set LayoutGravity in Java on a TextView

I'll tried for debug purposes to include them three times each with another gravity which does work even. So I assume everything is alright with my Layout and there has to be a Bug or something else I miss. Can someone give me a hint what I also can try, or what causes this problem?

Answer 1

将TextView的宽度设置为android:layout_width="fill_parent"然后可以使用myTextView.setGravity(Gravity.CENTER)编程方式设置它

Answer 2

You need to set the gravity of the LayoutParams object instead of the View itself:

TextView tv = new TextView(getApplicationContext());
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.FILL_PARENT);
lp.gravity = Gravity.CENTER;
tv.setLayoutParams(lp);

Answer 3

当你使用LinearLayout作为父级时，layout_gravity会出现在控件中但不控制内容的图片中，所以使用android:layout_gravity使用android:gravity 。