佈局文件:
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<CheckBox
android:id="@+id/cb"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="啓動後呈現對話框"></CheckBox>
</LinearLayout>
1.首先獲取SharedPreferences對象;
SharePreferences sharedPreferences = getSharedPreferences("aaa", Context.MODE_PRIVATE);
第一個參數的aaa是自己定義的,隨便叫,取值時候要用的。
2.獲取SharedPreferences.Editor對象;
SharedPreferences.Editor editor = sharedPreferences.edit();
用SharedPreferences對象調用edit()方法,
3.用Editor 存值;
editor.putBoolean("aaa", isChecked);
editor.commit();//切記一定要提交
一定要提交,一定要提交,一定要提交
4.取值:
boolean b=sharedPreferences.getBoolean("aaa", false)
以上就實現了存值和取值的過程;
下面有個代碼的實現可以參考下:
package com.example.myview;
import android.content.Context;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.TextView;
import androidx.appcompat.app.AlertDialog;
import androidx.appcompat.app.AppCompatActivity;
public class MainActivity extends AppCompatActivity {
private TextView textView;
private CheckBox cb;
private SharedPreferences sharedPreferences;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sharedPreferences = getSharedPreferences("aaa", Context.MODE_PRIVATE);
cb = findViewById(R.id.cb);
cb.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putBoolean("aaa", isChecked);
editor.commit();
}
});
cb.setChecked(sharedPreferences.getBoolean("aaa", false));
if (cb.isChecked()) {
AlertDialog builder = new AlertDialog.Builder(this).setTitle("你好").setMessage("歡迎使用我").setNegativeButton("取消",null).show();
}
}
}