Android應用中Toast的位置如何更改

<&#63;xml version="1.0" encoding="utf-8"&#63;>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="match_parent"
  android:layout_height="match_parent"
  android:orientation="vertical" >

  <Button
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:onClick="onClickDefaultToast"
    android:text="點擊顯示默認位置的Toast" />

  <Button
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:onClick="onClickCenterToast"
    android:text="點擊顯示居中位置的Toast" />


  <Button
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:onClick="onClickTopToast"
    android:text="點擊顯示居中上部位置的Toast" />

</LinearLayout>

package chengyujia.demo.aty;

import android.os.Bundle;
import android.view.Display;
import android.view.Gravity;
import android.view.View;
import android.widget.Toast;
import chengyujia.demo.R;

public class ToastActivity extends BaseActivity {

  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_toast);
  }

  public void onClickDefaultToast(View v) {
    Toast.makeText(this, "默認位置的Toast", Toast.LENGTH_LONG).show();
  }

  public void onClickCenterToast(View v) {
    Toast toast = Toast.makeText(this, "居中位置的Toast", Toast.LENGTH_LONG);
    toast.setGravity(Gravity.CENTER, 0, 0);
    toast.show();
  }

  public void onClickTopToast(View v) {
    Display display = getWindowManager().getDefaultDisplay();
    // 獲取屏幕高度
    int height = display.getHeight();
    Toast toast = Toast.makeText(this, "居中上部位置的Toast", Toast.LENGTH_LONG);
    // 這里給了一個1/4屏幕高度的y軸偏移量
    toast.setGravity(Gravity.TOP, 0, height / 4);
    toast.show();
  }
}