[Android Studio] -- Day 3 Activity练习

前言

今天将针对activity的跳转来复习复习

正文

这次采用bundle来传值，并区分startActivity()和startActivityForResult()

startActivity()

从Activity1跳转到Activity2

Activity1
按下按钮後进行跳转

button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                temp = editText.getText().toString();
                bundle.putString("input",temp);
                intent.putExtras(bundle);
                startActivity(intent);

            }
        });

Activity2
显示文字，按下按钮後返回(关闭Activity2)

        textView=findViewById(R.id.Text);
        button=findViewById(R.id.b2);

        Bundle bundle=this.getIntent().getExtras();
        String msg=bundle.getString("input");
        textView.setText(""+msg);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                finish();
            }
        });

startActivityForResult()

从Activity1跳转到Activity2并等待Activity2结果

Activity1
按下按钮後进行跳转

button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                temp = editText.getText().toString();
                bundle.putString("input",temp);
                intent.putExtras(bundle);
                //更改
                startActivityForResult(intent,0);

            }
        });

用来接收Activity2回传回来的值，显示在textView上

@Override
    protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        //333是自订义，要跟Activity2一样就行
        if(resultCode==333){
            Bundle bundle=data.getExtras();
            String msg=bundle.getString("input");
            textView.setText(""+msg);
        }

    }

Activity2
显示文字，按下按钮把刚刚放在intent的东西传过去Activity1後关闭Activity2

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                MainActivity2.this.setResult(333,intent);
                finish();
            }
        });