七、記住密碼自動登入
1.activity_main.xml:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<EditText
android:id="@+id/editText1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10" >
<requestFocus />
</EditText>
<EditText
android:id="@+id/editText2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:ems="10" />
<CheckBox
android:id="@+id/checkBox1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="自動登入" />
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="登入" />
</LinearLayout>
2.activity_two.xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".TwoActivity" >
<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginTop="22dp"
android:text="清除資料" />
</RelativeLayout>
3.在MainActivity裡邊寫:
package com.ebw.sp;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.CheckBox;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends Activity implements OnClickListener {
private SharedPreferences sp;
private EditText user;
private EditText pass;
private CheckBox box;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// 1獲取sp (檔名,檔案訪問許可權)
sp = getSharedPreferences("login", Context.MODE_PRIVATE);
//7判斷是否自動登入
if (sp.getBoolean("自動登入", false)) {
//跳轉頁面
startActivity(new Intent(MainActivity.this, TwoActivity.class));
finish();//5分
return;
}
// 2找控制元件
user = (EditText) findViewById(R.id.editText1);
pass = (EditText) findViewById(R.id.editText2);
box = (CheckBox) findViewById(R.id.checkBox1);
findViewById(R.id.button1).setOnClickListener(this);
//8記住密碼並顯示賬號和密碼
String userT = sp.getString("user", "");
String passT = sp.getString("pass", "");
//9顯示
user.setText(userT);
pass.setText(passT);
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.button1:
// 3點選按鈕獲取使用者名稱密碼 //.trim()去除空格
String userText = user.getText().toString().trim();
String passText = pass.getText().toString().trim();
// 4判斷輸入框是否有值
if (userText.equals("") || passText.equals("")) {
Toast.makeText(MainActivity.this, "使用者名稱密碼不能為空", 0).show();
return;//停止執行
}
//5如果密碼和賬號不為空 就存值登入
Editor edit = sp.edit();
edit.putBoolean("自動登入", box.isChecked());
edit.putString("user", userText);
edit.putString("pass", passText);
edit.commit();
//6跳轉頁面
startActivity(new Intent(MainActivity.this, TwoActivity.class));
finish();//5分
break;
}
}
}
4.在TwoActivity裡邊寫:
package com.ebw.sp;
import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
public class TwoActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_two);
//清除資料
findViewById(R.id.button1).setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
//獲取登入的sp(注意要求 引數一樣)
SharedPreferences sp = getSharedPreferences("login", Context.MODE_PRIVATE);
//清除資料'
sp.edit().clear().commit();
}
});
}
}