我想使用android中的按钮隐藏和取消隐藏文本； 该代码是正确的，但仍然无法正常工作

Question

Here is the xml file

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_hide"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.andrew.hide.Hide">

    <TextView
        android:text="This is the text"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:layout_marginTop="81dp"
        android:id="@+id/textView"
        android:textSize="40sp"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true" />

    <Button
        android:text="Hide"
        android:layout_width="match_parent"
        android:layout_height="50dp"
        android:id="@+id/button"
        android:textSize="28sp"
        android:onClick="hide"
        android:layout_marginBottom="184dp" />

</RelativeLayout>

Here is the java file

package com.example.andrew.hide;

import android.app.Activity;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class Hide extends Activity {

    Button b1;
    TextView t1;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_hide);
        b1=(Button) findViewById(R.id.button);
        t1=(TextView) findViewById(R.id.textView);
        String text=b1.getText().toString();
    }

    public void hide(View view) {
        if (b1.getText().toString() == "Hide") {
            t1.setVisibility(View.INVISIBLE);
            b1.setText("Unhide");
        }
        if (b1.getText().toString() == "Unhide") {
            t1.setVisibility(View.VISIBLE);
            b1.setText("Hide");
        }
    }

}

I am new to android development , so ignore if this doubt is silly. I manually checked by using Log and I found that getText works perfectly Nothing happens whenever i click the button (b1 here),How do I fix this?

Answer 1

Why don't you simply check the TextView visibility and perform your actions based on that ? It's all the setters and getters right ?

b1.onClickListener(new OnClickListener() {
    if (t1.getVisibility() == View.Visible) {
       t1.setVisibilty(View.GONE);
    //--- your code
    } else {
       t1.setVisibilty(View.VISIBLE);
    //--- your code
    }
);

Answer 2

Use equals to compare strings.

Try this,

public void hide(View view) {
    String text = b1.getText().toString();
    if (text.equals("Hide")) {
        t1.setVisibility(View.INVISIBLE);
        b1.setText("Unhide");
    } else if (text.equals("Unhide")) {
        t1.setVisibility(View.VISIBLE);
        b1.setText("Hide");
    }
}