<?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"
android:orientation="vertical"
android:gravity="center"
tools:context=".MainActivity">
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="账号:"/>
<EditText
android:id="@+id/username"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:width="80dp"/>
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="密码:"/>
<EditText
android:id="@+id/password"
android:width="80dp"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
<Button
android:id="@+id/bt_insert"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="插入"/>
<Button
android:id="@+id/bt_query"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="查询"/>
<Button
android:id="@+id/bt_update"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="更新"/>
<Button
android:id="@+id/bt_delete"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="删除"/>
</LinearLayout>
<TextView
android:id="@+id/showText"
android:text="暂无数据"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
package com.sjzc.edu;
import android.content.Context;
import android.database.sqlite.SQLiteDatabase;
import android.database.sqlite.SQLiteOpenHelper;
public class MyHelper extends SQLiteOpenHelper {//继承SQLiteOpenHelper
public MyHelper(Context context) {
super(context, "itcast.db", null, 1);//参数3:游标工厂
}
//创建数据库
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL("CREATE TABLE information (_id INTEGER PRIMARY KEY AUTOINCREMENT,username VARCHAR(20),password VARCHAR(20))");
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}
}
package com.sjzc.edu;
import android.content.ContentValues;
import android.content.Context;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
private MyHelper myHelper;
private EditText et_username;
private EditText et_password;
private TextView showText;
private Button bt_query;
private Button bt_insert;
private Button bt_update;
private Button bt_delete;
private String username;
private String password;
private SQLiteDatabase db;
private ContentValues values;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//创建数据库
myHelper= new MyHelper(this);
initView();//初始化控件
}
private void initView() {
et_username = findViewById(R.id.username);
et_password = findViewById(R.id.password);
showText = findViewById(R.id.showText);
bt_delete = findViewById(R.id.bt_delete);
bt_insert = findViewById(R.id.bt_insert);
bt_query = findViewById(R.id.bt_query);
bt_update = findViewById(R.id.bt_update);
bt_update.setOnClickListener(MainActivity.this);
bt_delete.setOnClickListener(MainActivity.this);
bt_query.setOnClickListener(MainActivity.this);
bt_insert.setOnClickListener(MainActivity.this);
}
@Override
public void onClick(View v) {
switch (v.getId()){
case R.id.bt_insert://添加
username = et_username.getText().toString();
password = et_password.getText().toString();
db = myHelper.getReadableDatabase();//获取可读的数据库对象
values = new ContentValues();
values.put("username",username);
values.put("password",password);
db.insert("information",null,values);
db.close();
Toast.makeText(MainActivity.this,"插入成功",Toast.LENGTH_LONG).show();
break;
case R.id.bt_query://查询
db = myHelper.getReadableDatabase();//获取可读的数据库对象
Cursor cursor = db.query("information", null, null, null, null, null, null);//返回一个结果集
if (cursor.getCount()==0){
//没有查到数据
Toast.makeText(MainActivity.this,"没有查到数据",Toast.LENGTH_LONG).show();
showText.setText("没有查到数据");
}else{
cursor.moveToFirst();
Toast.makeText(MainActivity.this,cursor.getString(1),Toast.LENGTH_LONG).show();
showText.setText("Username:"+cursor.getString(1)+",Password:"+cursor.getString(2));//每行数据有两列,分别为username和password
while (cursor.moveToNext()){
showText.append("\n"+"Username:"+cursor.getString(1)+",Password:"+cursor.getString(2));
}
}
db.close();//用完了要关闭
break;
case R.id.bt_update://更新
username = et_username.getText().toString();
db = myHelper.getReadableDatabase();//获取可读的数据库对象
values = new ContentValues();
values.put("password","987654");//要更新的字段和内容
db.update("information",values,"username = ?",new String[]{username});
db.close();
break;
case R.id.bt_delete://删除
db = myHelper.getReadableDatabase();
db.delete("information",null,null);//删除所有
Toast.makeText(MainActivity.this,"删除成功",Toast.LENGTH_LONG).show();
showText.setText("无数据");
db.close();
break;
}
}import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.support.v7.widget.AppCompatImageView;
import android.util.AttributeSet;
/**
* Created by zachary on 2019/04/08.
* 圆形ImageView
*/
public class MusicView extends AppCompatImageView {
private Paint paint;
public MusicView(Context context) {
this(context,null);
}
public MusicView(Context context, AttributeSet attrs) {
this(context, attrs,0);
}
public MusicView(Context context, AttributeSet attrs, int defStyleAttr) {
super(context, attrs, defStyleAttr);
paint = new Paint();
}
@Override
protected void onDraw(Canvas canvas) {
//获取图像资源
Drawable drawable = getDrawable();
if (null != drawable) {
Bitmap bitmap = ((BitmapDrawable) drawable).getBitmap();
Bitmap b = getCircleBitmap(bitmap);
//上层
final Rect rectSrc = new Rect(0, 0, b.getWidth(), b.getHeight());
//下层
final Rect rectDest = new Rect(0,0,getWidth(),getHeight());
paint.reset();
canvas.drawBitmap(b, rectSrc, rectDest, paint);
} else {
super.onDraw(canvas);
}
}
/**
* 获取圆形图片方法
* @param bitmap
* @return Bitmap
*/
private Bitmap getCircleBitmap(Bitmap bitmap) {
Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
bitmap.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(output);
final int color = 0xffffffff;
final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
//设置抗锯齿
paint.setAntiAlias(true);
canvas.drawARGB(0, 0, 0, 0);
paint.setColor(color);
int x = bitmap.getWidth();
//圆形的大小
canvas.drawCircle(x / 2, x / 2, x / 2, paint);
//PorterDuff.Mode.SRC_IN模式组合效果
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(bitmap, rect, rect, paint);
return output;
}
}
import android.animation.ObjectAnimator;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Build;
import android.support.annotation.RequiresApi;
import android.support.v7.widget.AppCompatImageView;
import android.util.AttributeSet;
import android.view.animation.LinearInterpolator;
/**
* Created by zachary on 2019/04/08.
* 圆形ImageView,旋转操作(属性动画ObjectAnimator)
*/
public class MusicView extends AppCompatImageView {
private ObjectAnimator objectAnimator;
public static final int STATE_PLAYING = 1; //正在播放
public static final int STATE_PAUSE = 2; //暂停
public static final int STATE_STOP = 3; //停止
public int state;
private Paint paint;
public MusicView(Context context) {
this(context,null);
}
public MusicView(Context context, AttributeSet attrs) {
this(context, attrs,0);
}
public MusicView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
paint = new Paint();
init();
}
private void init(){
state = STATE_STOP;
//添加旋转动画,旋转中心默认为控件中点
objectAnimator = ObjectAnimator.ofFloat(this, "rotation", 0f, 360f);
//设置动画时间:3s
objectAnimator.setDuration(3000);
//动画:时间线性渐变
objectAnimator.setInterpolator(new LinearInterpolator());
objectAnimator.setRepeatCount(ObjectAnimator.INFINITE);
objectAnimator.setRepeatMode(ObjectAnimator.RESTART);
}
/**
* 绘制圆形图片
*/
@Override
protected void onDraw(Canvas canvas) {
Drawable drawable = getDrawable();
if (null != drawable) {
Bitmap bitmap = ((BitmapDrawable) drawable).getBitmap();
Bitmap b = getCircleBitmap(bitmap);
//上层
final Rect rectSrc = new Rect(0, 0, b.getWidth(), b.getHeight());
//下层
final Rect rectDest = new Rect(0,0,getWidth(),getHeight());
paint.reset();
canvas.drawBitmap(b, rectSrc, rectDest, paint);
} else {
super.onDraw(canvas);
}
}
/**
* 获取圆形图片方法
* @param bitmap
* @return Bitmap
*/
private Bitmap getCircleBitmap(Bitmap bitmap) {
Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
bitmap.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(output);
final int color = 0xff424242;
final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
paint.setAntiAlias(true);
canvas.drawARGB(0, 0, 0, 0);
paint.setColor(color);
int x = bitmap.getWidth();
canvas.drawCircle(x / 2, x / 2, x / 2, paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(bitmap, rect, rect, paint);
return output;
}
@RequiresApi(api = Build.VERSION_CODES.KITKAT)
public void playMusic(){
if(state == STATE_STOP){
objectAnimator.start(); //动画开始
state = STATE_PLAYING;
}else if(state == STATE_PAUSE){
objectAnimator.resume(); //动画重新开始
state = STATE_PLAYING;
}else if(state == STATE_PLAYING){
objectAnimator.pause(); //动画暂停
state = STATE_PAUSE;
}
}
public void stopMusic(){
objectAnimator.end(); //动画结束
state = STATE_STOP;
}
}
}
2019最新黑马javaee第49期全套无加密项目实战(完整)
猜你喜欢
转载自blog.csdn.net/weixin_44937580/article/details/90026869
今日推荐
周排行