2019/0605/Java介面實作&結束+安卓工作室(整合Layout與Java)Intent意圖&Bundle包裹

#Java

前情提要類別

##繼承介面實作 / 抽象類別 override

多型呼叫處理

作業五講解

下午 Inttent 資料傳遞畫面整合

意圖與程式生命週期

獨立活動沒有資料交換前景轉背景轉B畫面

相依活動傳遞資料至下一個活動

修改前最好做備份

APP 很多 Activity 切換利用 Intent

Values dimens.xml

## alt + enter 快速引入package

這個就沒有傳遞參數

Intent 意圖使用方式

###E:\android\Intent01\app\src\main\java\com\example\intent01\MainActivity.java


package com.example.intent01;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.content.Intent;
import android.view.View;


public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    public void button_Click(View v){
        Intent intent = new Intent(this,SecondActivity.class);
        startActivity(intent);
    }

    public void button01_Click(View v){
        Intent intent = new Intent(this,ThreeActivity.class);
        startActivity(intent);
    }


}

###E:\android\Intent01\app\src\main\java\com\example\intent01\SecondActivity.java

package com.example.intent01;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;

public class SecondActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_second);
    }

    public void button2_Click(View v){
        finish();
    }
}

###E:\android\Intent01\app\src\main\java\com\example\intent01\ThreeActivity.java

package com.example.intent01;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;

public class ThreeActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_three);
    }

    public void button2_Click(View v){
        finish();
    }
}

自動在讀取完後顯示要寫在 onCreate

bundle 包裹使用方式

###FActivity

package com.example.intent02;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.TextView;

public class FActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_f);
        convertTempture();
    }

    public void convertTempture(){
        int c;
        double f = 0.0;
        Bundle bundle = this.getIntent().getExtras();

        if(bundle != null){
            c = Integer.parseInt(bundle.getString("TEMPC"));
            f = (9.0 * c) / 5 + 32;
            TextView o = findViewById(R.id.lblOutput);
            o.setText("華氏溫度:"+Double.toString(f));
        }
    }




    public  void button2_Click(View V){
        finish();
    }
}

### MainActivity

package com.example.intent02;

import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
    }

    public void button_Click(View V){
        EditText txtC = findViewById(R.id.txtC);
        Intent intent = new Intent(this,FActivity.class);
        Bundle bundle = new Bundle();
        bundle.putString("TEMPC",txtC.getText().toString());
        intent.putExtras(bundle);
        startActivity(intent);
    }
}