android练习：星级评分条，吐司打印居中显示

android练习：星级评分条，吐司打印居中显示

RatingBar：星级条
seekBar：拖动条
Progress：进度条
rating：默认点亮几颗
吐司打印居中显示主要语法
Toast toast=Toast.makeText(getApplicationContext(),输出内容，Toast.LENGTH_LONG);
toast.setGravity(Gravity.CENTER,0,0);//居中显示吐司打印
toast.show();//显示结果
注意：每次都是半颗半颗的显示
xml：

<RatingBar
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:rating="5"
    android:layout_gravity="center_horizontal"
    android:id="@+id/rb"/>
    <Button
        android:id="@+id/btn"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:text="开始评价"
        android:textSize="20dp"/>

java：

package com.example.acer.gentupian;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.RatingBar;
import android.widget.Toast;
public class MainActivity extends ActionBarActivity {
    private RatingBar ratingBar;

    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ratingBar = (RatingBar) findViewById(R.id.rb);
        Button btn = (Button) findViewById(R.id.btn);
        btn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                float rbing = ratingBar.getRating();
                Toast toast=Toast.makeText(getApplicationContext(),"你点亮了" + rbing + "颗数星星",Toast.LENGTH_LONG);
                toast.setGravity(Gravity.CENTER,0,0);//居中显示吐司打印
                toast.show();
                //Toast.makeText(MainActivity.this, "你点亮了" + rbing + "颗数星星", Toast.LENGTH_LONG).show();

            }
        });
    }
}

结果：

附加：Button的形状设置
使用shape来自定义按钮形状：
drawable下新建btn_shape.xml

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
    <corners android:radius="10dp"/><!--设置圆角-->
    <solid android:color="@color/grey"/><!--设置背景颜色-->
</shape>

<Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="圆角图片"
        android:background="@drawable/btn_shape"
        />