android - 在验证用户名和密码时找不到符号 setError()

Question

当我尝试验证我的用户名和密码时，我收到一条错误消息，提示未找到 setError，你能帮我找出我的错误吗？我在 androidstudio1.2.2 中执行了此操作

登录.java

package com.example.poornima.bookmyticket;

import com.example.poornima.bookmyticket.util.SystemUiHider;

import android.annotation.TargetApi;
import android.app.Activity;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.os.Handler;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import android.view.Menu;
import android.widget.TextView;
import android.widget.Toast;


/**
 * An example full-screen activity that shows and hides the system UI (i.e.
 * status bar and navigation/system bar) with user interaction.
 *
 * @see SystemUiHider
 */
public class login extends Activity implements View.OnClickListener {
    private Button bLogin, bRegister;
   private  EditText eusername, epassword;


    /**
     * Whether or not the system UI should be auto-hidden after
     * {@link #AUTO_HIDE_DELAY_MILLIS} milliseconds.
     */
    private static final boolean AUTO_HIDE = true;

    /**
     * If {@link #AUTO_HIDE} is set, the number of milliseconds to wait after
     * user interaction before hiding the system UI.
     */
    private static final int AUTO_HIDE_DELAY_MILLIS = 3000;

    /**
     * If set, will toggle the system UI visibility upon interaction. Otherwise,
     * will show the system UI visibility upon interaction.
     */
    private static final boolean TOGGLE_ON_CLICK = true;

    /**
     * The flags to pass to {@link SystemUiHider#getInstance}.
     */
    private static final int HIDER_FLAGS = SystemUiHider.FLAG_HIDE_NAVIGATION;

    /**
     * The instance of the {@link SystemUiHider} for this activity.
     */
    private SystemUiHider mSystemUiHider;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_login);

        final View controlsView = findViewById(R.id.fullscreen_content_controls);
        final View contentView = findViewById(R.id.fullscreen_content);

        bLogin = (Button) findViewById(R.id.bLogin);
        bRegister = (Button) findViewById(R.id.bRegister);
        eusername = (EditText) findViewById(R.id.eusername);
        epassword = (EditText) findViewById(R.id.epassword);
        bLogin.setOnClickListener(this);
        bRegister.setOnClickListener(this);
        // Set up an instance of SystemUiHider to control the system UI for
        // this activity.
        mSystemUiHider = SystemUiHider.getInstance(this, contentView, HIDER_FLAGS);
        mSystemUiHider.setup();
        mSystemUiHider
                .setOnVisibilityChangeListener(new SystemUiHider.OnVisibilityChangeListener() {
                    // Cached values.
                    int mControlsHeight;
                    int mShortAnimTime;

                    @Override
                    @TargetApi(Build.VERSION_CODES.HONEYCOMB_MR2)
                    public void onVisibilityChange(boolean visible) {
                        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB_MR2) {
                            // If the ViewPropertyAnimator API is available
                            // (Honeycomb MR2 and later), use it to animate the
                            // in-layout UI controls at the bottom of the
                            // screen.
                            if (mControlsHeight == 0) {
                                mControlsHeight = controlsView.getHeight();
                            }
                            if (mShortAnimTime == 0) {
                                mShortAnimTime = getResources().getInteger(
                                        android.R.integer.config_shortAnimTime);
                            }
                            controlsView.animate()
                                    .translationY(visible ? 0 : mControlsHeight)
                                    .setDuration(mShortAnimTime);
                        } else {
                            // If the ViewPropertyAnimator APIs aren't
                            // available, simply show or hide the in-layout UI
                            // controls.
                            controlsView.setVisibility(visible ? View.VISIBLE : View.GONE);
                        }

                        if (visible && AUTO_HIDE) {
                            // Schedule a hide().
                            delayedHide(AUTO_HIDE_DELAY_MILLIS);
                        }
                    }
                });

        // Set up the user interaction to manually show or hide the system UI.
        contentView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (TOGGLE_ON_CLICK) {
                    mSystemUiHider.toggle();
                } else {
                    mSystemUiHider.show();
                }
            }
        });

        // Upon interacting with UI controls, delay any scheduled hide()
        // operations to prevent the jarring behavior of controls going away
        // while interacting with the UI.

    }


    @Override
    public void onClick(View arg0) {
        final String username = eusername.getText().toString();
        if (!isValidUsername(username)) {
            username.setError("Invalid Email");
        }

        final String password = epassword.getText().toString();
        if (!isValidPassword(password)) {
            password.setError("Invalid Password");

        }

    }


    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);

        // Trigger the initial hide() shortly after the activity has been
        // created, to briefly hint to the user that UI controls
        // are available.
        delayedHide(100);
    }


    /**
     * Touch listener to use for in-layout UI controls to delay hiding the
     * system UI. This is to prevent the jarring behavior of controls going away
     * while interacting with activity UI.
     */
    View.OnTouchListener mDelayHideTouchListener = new View.OnTouchListener() {
        @Override
        public boolean onTouch(View view, MotionEvent motionEvent) {
            if (AUTO_HIDE) {
                delayedHide(AUTO_HIDE_DELAY_MILLIS);
            }
            return false;
        }
    };

    Handler mHideHandler = new Handler();
    Runnable mHideRunnable = new Runnable() {
        @Override
        public void run() {
            mSystemUiHider.hide();
        }
    };

    /**
     * Schedules a call to hide() in [delay] milliseconds, canceling any
     * previously scheduled calls.
     */
    private void delayedHide(int delayMillis) {
        mHideHandler.removeCallbacks(mHideRunnable);
        mHideHandler.postDelayed(mHideRunnable, delayMillis);
    }

    private boolean isValidUsername(String username) {
        if (username != null && username.length() > 4) {
            return true;
        }
        return false;
    }

    private boolean isValidPassword(String pass) {
        if (pass != null && pass.length() > 6) {
            return true;
        }
        return false;
    }
}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
    android:layout_height="match_parent" android:background="@drawable/train1"
    tools:context="gss.bookmyticket.LOGIN">

<LinearLayout
    android:id="@+id/fullscreen_content_controls"
    style="?metaButtonBarStyle"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom|center_horizontal"
    android:orientation="horizontal"
    tools:ignore="UselessParent" >
</LinearLayout>
<TextView
android:id="@+id/fullscreen_content"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center"
android:keepScreenOn="true"
android:text=" "
android:textStyle="bold"
android:layout_below="@+id/fullscreen_content_controls"
android:layout_alignParentStart="true" />


<ImageButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/imageButton"
android:src="@drawable/image1"
android:background="@android:color/transparent"
android:layout_below="@+id/fullscreen_content_controls"
android:layout_centerHorizontal="true" />

<EditText
android:layout_width="300dp"
android:layout_height="50dp"
android:id="@+id/eusername"
android:background="@drawable/s1"
android:textColor="#78909C"
android:hint="USERNAME"
android:gravity="center"
android:layout_marginTop="46dp"
android:layout_below="@+id/imageButton"
android:layout_centerHorizontal="true" />

<EditText
android:layout_width="300dp"
android:layout_height="50dp"
android:inputType="textPassword"
android:gravity="center"
android:background="@drawable/s1"
android:ems="10"
android:id="@+id/epassword"
android:hint="PASSWORD"
android:textColor="#78909C"
android:layout_marginTop="60dp"
android:layout_below="@+id/eUSERNAME1"
android:layout_alignEnd="@+id/eUSERNAME1"
android:layout_alignStart="@+id/eUSERNAME1" />

<Button
android:layout_width="120dp"
android:background="@drawable/s2"
android:layout_height="wrap_content"
android:text="SIGN IN"
android:id="@+id/bLogin"
android:layout_alignTop="@+id/bRegister"
android:layout_alignStart="@+id/ePASSWORD1" />

<Button
android:layout_width="120dp"
android:layout_height="wrap_content"
android:text="SIGN UP"
android:background="@drawable/s4"
android:id="@+id/bRegister"
android:layout_alignParentBottom="true"
android:layout_alignEnd="@+id/ePASSWORD1"
android:layout_marginBottom="56dp" />

<ImageView
android:layout_width="25dp"
android:layout_height="25dp"
android:id="@+id/imageView"
android:src="@drawable/user"
android:layout_marginLeft="10dp"
android:paddingLeft="0dp"
android:paddingRight="0dp"
android:paddingTop="0dp"
android:paddingBottom="0dp"
android:layout_alignTop="@+id/eUSERNAME1"
android:layout_alignStart="@+id/eUSERNAME1"
android:layout_alignBottom="@+id/eUSERNAME1" />

<ImageView
android:layout_width="25dp"
android:layout_height="25dp"
android:src="@drawable/i3"
android:layout_marginLeft="0dp"
android:id="@+id/imageView2"
android:layout_alignTop="@+id/ePASSWORD1"
android:layout_alignBottom="@+id/ePASSWORD1"
android:layout_alignStart="@+id/imageView" />


    </RelativeLayout>

Answer 1

因为 setError 是 TextView 而不是 String 的方法

改变

@Override
public void onClick(View arg0) {
    final String username = eusername.getText().toString();
    if (!isValidUsername(username)) {
        username.setError("Invalid Email");
    }

    final String password = epassword.getText().toString();
    if (!isValidPassword(password)) {
        password.setError("Invalid Password");

    }
}

与

@Override
public void onClick(View arg0) {
    final String username = eusername.getText().toString();
    if (!isValidUsername(username)) {
        eusername.setError("Invalid Email");
    }

    final String password = epassword.getText().toString();
    if (!isValidPassword(password)) {
        epassword.setError("Invalid Password");

    }

}