# Android

## Add permission for connect to net
set in manifest

<uses-permission android:name="android.permission.INTERNET"/>

## Add permission for connect to http
set in manifest

<application
android:usesCleartextTraffic="true"
>

## Add permission for old version
set in build.gradle

minSdkVersion 24

## Connect Android to API
*text =>save json(String) from API

    void connect(){
        new Thread(new Runnable() {
            @Override
            public void run() {
                try {
                    URL url=new URL("http://192.168.88.143:90/api/getvalue");
                    HttpURLConnection httpURLConnection=(HttpURLConnection) url.openConnection();
                    try {
                        BufferedReader bufferedReader=new BufferedReader(new InputStreamReader(httpURLConnection.getInputStream()));
                        StringBuilder stringBuilder=new StringBuilder();
                        String str;
                        while ((str=bufferedReader.readLine())!=null){
                            stringBuilder.append(str).append("\n");
                        }
                        text=stringBuilder.toString();
                    }catch (Exception e){
                    }finally {
                        httpURLConnection.disconnect();
                    }

                } catch (MalformedURLException e) {
                    e.printStackTrace();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }).start();
    }

#### get JsonArray
`JSONArray jsonArray=new JSONArray(text);`
#### getjsonObject

for(int i=0;i<jsonArray.length();i++)
JSONObject jsonObject=jsonArray.getJSONObject(i);

## Global Variable
Put Variable on application

<application android:name=".Values">

public class Values extends Application {
    private String Name;
    private  int Actype;
    public void setName(String name){ Name=name; }
    public void setactype(int actype){ Actype=actype; }
    public String getName(){ return Name; }
    public int getActype(){ return Actype; }
}

`Values values=(Values)getApplicationContext();`
`values.setName();`
`values.getName();`
## Custom list and set click event(Create Alterdialog)

public class MainActivity extends AppCompatActivity {
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ListView lv1=findViewById(R.id.lv1);
        Button btn1=findViewById(R.id.btn1);
        final String[] str1={"A","B","C","D","E","F","G"};
        final String[] str2={"1","2","3","4","5","6","7"};
        adapt adapt=new adapt(this);
        adapt.getString(str1,str2);
        lv1.setAdapter(adapt);
        lv1.setOnItemClickListener(new AdapterView.OnItemClickListener() {
            int[] imglist={R.drawable.p1,R.drawable.p2,R.drawable.p3,R.drawable.p4,R.drawable.p5,R.drawable.p6,R.drawable.p7};
            @Override
            public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
            //Create AlterDlalog
                AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this);
                LayoutInflater inflater = MainActivity.this.getLayoutInflater();
                View myview=inflater.inflate(R.layout.mylayout2,null);
                TextView tv31=myview.findViewById(R.id.tv31);
                tv31.setText(str1[position]);
                TextView tv32=myview.findViewById(R.id.tv32);
                tv32.setText(str2[position]);
                ImageView imgv31=myview.findViewById(R.id.imgv31);
                imgv31.setImageResource(imglist[position]);
                builder.setView(myview);
                AlertDialog dialog = builder.create();
                dialog.show();
            }
        });
    }
}
class adapt extends BaseAdapter{
    int[] imglist={R.drawable.p1,R.drawable.p2,R.drawable.p3,R.drawable.p4,R.drawable.p5,R.drawable.p6,R.drawable.p7};
    String[] str1;
    String[] str2;
    Context context;
    LayoutInflater layoutInflater;
    public adapt(Context c) {
        context=c;
        layoutInflater = LayoutInflater.from(c);
    }
    public void getString(String[] Str1,String[] Str2){
        str1=Str1;
        str2=Str2;
    }
    @Override
    public int getCount() {
        return str1.length;
    }
    @Override
    public Object getItem(int position) {
        return str1[position];
    }
    @Override
    public long getItemId(int position) {
        return position;
    }
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        convertView = layoutInflater.inflate(R.layout.mylayout,null);
        TextView tv1=convertView.findViewById(R.id.tv21);
        TextView tv2=convertView.findViewById(R.id.tv22);
        ImageView imgv=convertView.findViewById(R.id.imgv21);
        tv1.setText(str1[position]);
        tv2.setText(str2[position]);
        imgv.setImageResource(imglist[position]);
        return  convertView;
    }
}

# Layout
顯示的文字為致中對齊:
`android:gravity="center"`

在VIEW上的顯示為置中:
`android:layout_gravity="center"`
padding & Margin: