안드로이드 수업 1일차 -버튼

- 버튼 

: 원하는 문장 입력 후 BUTTON을 짧게 누르면 글자가 뜨고, 길게 누르면 입력한 문장이 삭제 되는 코드  

 

첫 화면

hihihi친 후 BUTTON누르면 뜸 

BUTTON 길게 누르면 입력한 글 지워짐 

 

- android:hint="원하는 문장을 입력하세요" 를 하면 위의 화면처럼 나옴. 

 

 

<activity_main.xml>

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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"
    tools:context=".MainActivity">

    <TextView
        android:id="@+id/textView"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="292dp"
        android:text="Hello !!!"
        android:textColor="#3F51B5"
        android:visibility="invisible"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <Button
        android:id="@+id/testButton"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="clickTestButton"
        android:text="Button"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <EditText
        android:id="@+id/editText"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:ems="10"
        android:inputType="textPersonName|text"
        android:hint="원하는 문장을 입력하세요"
        app:layout_constraintEnd_toStartOf="@+id/testButton"
        app:layout_constraintStart_toStartOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

 

<MainActivity.java>

package com.example.myapplication;

import androidx.appcompat.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 {
    Button testButton;
    TextView textView;
    EditText editText;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        testButton = findViewById(R.id.testButton);
        testButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                String temp = editText.getText().toString();
                textView.setText(temp);
                textView.setVisibility(View.VISIBLE);


            }
        });

        testButton.setOnLongClickListener(new View.OnLongClickListener() {
            @Override
            public boolean onLongClick(View v) {
                editText.setText("");


                return false;
            }
        });

        editText = findViewById(R.id.editText);
        textView = findViewById(R.id.textView);

    }