1-系统方案A(系统方案演示和运行第一个Android程序,ListView显示数据,删除数据)

系统教程初步要做到的就是12节和13节所演示的

12节：  https://www.cnblogs.com/yangfengwu/p/9966702.html

13节：  https://www.cnblogs.com/yangfengwu/p/9966901.html

https://www.cnblogs.com/yangfengwu/p/9065406.html   安装Android Studio

https://www.cnblogs.com/yangfengwu/p/9142929.html    导入工程

          

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 APP已经能运行了。。。

因为开发这个系统需要一些jar包，所以导入用到的jar包

 

 

 

 

 现在测试显示几个数据

public class MainActivity extends AppCompatActivity {

    ListView listView1;
    static ArrayList<String> ArrayListClientId = new ArrayList<String>();//存储ListView的数据
    ArrayAdapter<String> adapter;//为ListView添加一个适配器
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ArrayListClientId.add("1");
        ArrayListClientId.add("2");
        ArrayListClientId.add("3");

        listView1 = findViewById(R.id.ListView1);
        adapter = new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_list_item_1,ArrayListClientId);
        listView1.setAdapter(adapter);
    }
}

 

 

                   

 再做一个长按的操作

 

 然后自己可以试一试用自己的手指长按和点击

         

 所以就做一个变量控制下，长按以后别执行点击里面的

public class MainActivity extends AppCompatActivity {

    ListView listView1;
    static ArrayList<String> ArrayListClientId = new ArrayList<String>();//存储ListView的数据
    ArrayAdapter<String> adapter;//为ListView添加一个适配器
    boolean LongClick = false;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ArrayListClientId.add("1");
        ArrayListClientId.add("2");
        ArrayListClientId.add("3");

        listView1 = findViewById(R.id.ListView1);
        adapter = new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_list_item_1,ArrayListClientId);
        listView1.setAdapter(adapter);

        listView1.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                if (!LongClick){
                    Toast.makeText(MainActivity.this,"点击"+ArrayListClientId.get(position),Toast.LENGTH_SHORT).show();
                }
                LongClick = false;
            }
        });

        listView1.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
            @Override
            public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
                Toast.makeText(MainActivity.this,"长按"+ArrayListClientId.get(position),Toast.LENGTH_SHORT).show();
                LongClick = true;
                return false;
            }
        });
    }
}

可以自己再试一试

 然后在做一下长按删除

 

public class MainActivity extends AppCompatActivity {

    ListView listView1;
    static ArrayList<String> ArrayListClientId = new ArrayList<String>();//存储ListView的数据
    ArrayAdapter<String> adapter;//为ListView添加一个适配器
    boolean LongClick = false;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        ArrayListClientId.add("1");
        ArrayListClientId.add("2");
        ArrayListClientId.add("3");

        listView1 = findViewById(R.id.ListView1);
        adapter = new ArrayAdapter<String>(MainActivity.this,android.R.layout.simple_list_item_1,ArrayListClientId);
        listView1.setAdapter(adapter);

        listView1.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                if (!LongClick){
                    Toast.makeText(MainActivity.this,"点击"+ArrayListClientId.get(position),Toast.LENGTH_SHORT).show();
                }
                LongClick = false;
            }
        });

        listView1.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
            @Override
            public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
                Toast.makeText(MainActivity.this,"长按"+ArrayListClientId.get(position),Toast.LENGTH_SHORT).show();
                LongClick = true;
                showNormalDialog(position);
                return false;
            }
        });
    }

    private void showNormalDialog(final int index){
        final AlertDialog.Builder normalDialog = new AlertDialog.Builder(MainActivity.this);
        normalDialog.setTitle("删除设备");
        normalDialog.setMessage("确定要删除设备吗？");
        normalDialog.setPositiveButton("删除", new DialogInterface.OnClickListener() {
            @Override
            public void onClick(DialogInterface dialog, int which) {
                ArrayListClientId.remove(index);
                adapter.notifyDataSetChanged();
            }
        });
        normalDialog.setNegativeButton("取消", new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                    }
                });
        normalDialog.show();// 显示
    }
}

     

 好了这是第一节