text 2 Github上回购，搜索

Posted 2021-05-03

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:app="http://schemas.android.com/apk/res-auto">
    <item
        android:id="@+id/action_search"
        android:orderInCategory="1"
        app:showAsAction="ifRoom"
        android:title="@string/search"/>
</menu>

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:orientation="vertical"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    tools:context="com.example.android.datafrominternet.MainActivity">

    <EditText
        android:id="@+id/et_search_box"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:hint="Enter a query, then click Search"
        android:textSize="22sp" />

    <TextView
        android:id="@+id/tv_url_display"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginTop="8dp"
        android:text="Click search and your URL will show up here!"
        android:textSize="22sp" />

    <!--Wrap the ScrollView in a FrameLayout-->
    <!--Make the width and height of the FrameLayout match_parent-->
    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <ScrollView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="16dp">

            <TextView
                android:id="@+id/tv_github_search_results_json"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="Make a search!"
                android:textSize="18sp" />
        </ScrollView>

        <!--Add a TextView to display an error message-->
        <!--Set the text size to 22sp-->
        <!--Give the TextView an id of @+id/tv_error_message_display-->
        <!--Set the layout_height and layout_width to wrap_content-->
        <!--Add 16dp of padding to the error display -->
        <!--Use your strings.xml error message to set the text for the error message-->
        <!--Set the visibility of the view to invisible-->
        <!--Make this TextView a child of the FrameLayout the you added above-->
        <TextView
            android:id="@+id/tv_error_message_display"
            android:textSize="22sp"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:padding="16dp"
            android:text="@string/error_message"
            android:visibility="invisible" />

        <!--Add a ProgressBar to indicate loading to your users-->
        <!--Give the ProgressBar an id of @+id/pb_loading_indicator-->
        <!--Set the layout_height and layout_width to 42dp-->
        <!--Set the layout_gravity to center-->
        <!--Set the visibility of the ProgressBar to invisible-->
        <!--Make this ProgressBar a child of the FrameLayout that you added above-->
        <ProgressBar
            android:id="@+id/pb_loading_indicator"
            android:layout_height="42dp"
            android:layout_width="42dp"
            android:layout_gravity="center"
            android:visibility="invisible" />
    </FrameLayout>
</LinearLayout>

package com.example.android.datafrominternet.utilities;

import android.net.Uri;

import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Scanner;

/**
 * These utilities will be used to communicate with the network.
 */
public class NetworkUtils {

    final static String GITHUB_BASE_URL =
            "https://api.github.com/search/repositories";

    final static String PARAM_QUERY = "q";

    /*
     * The sort field. One of stars, forks, or updated.
     * Default: results are sorted by best match if no field is specified.
     */
    final static String PARAM_SORT = "sort";
    final static String sortBy = "stars";

    /**
     * Builds the URL used to query GitHub.
     *
     * @param githubSearchQuery The keyword that will be queried for.
     * @return The URL to use to query the GitHub.
     */
    public static URL buildUrl(String githubSearchQuery) {
        Uri builtUri = Uri.parse(GITHUB_BASE_URL).buildUpon()
                .appendQueryParameter(PARAM_QUERY, githubSearchQuery)
                .appendQueryParameter(PARAM_SORT, sortBy)
                .build();

        URL url = null;
        try {
            url = new URL(builtUri.toString());
        } catch (MalformedURLException e) {
            e.printStackTrace();
        }

        return url;
    }

    /**
     * This method returns the entire result from the HTTP response.
     *
     * @param url The URL to fetch the HTTP response from.
     * @return The contents of the HTTP response.
     * @throws IOException Related to network and stream reading
     */
    public static String getResponseFromHttpUrl(URL url) throws IOException {
        HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
        try {
            InputStream in = urlConnection.getInputStream();

            Scanner scanner = new Scanner(in);
            scanner.useDelimiter("\\A");

            boolean hasInput = scanner.hasNext();
            if (hasInput) {
                return scanner.next();
            } else {
                return null;
            }
        } finally {
            urlConnection.disconnect();
        }
    }
}

package com.example.android.datafrominternet;

import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;
import android.widget.ProgressBar;
import android.widget.TextView;

import com.example.android.datafrominternet.utilities.NetworkUtils;

import java.io.IOException;
import java.net.URL;

public class MainActivity extends AppCompatActivity {

    private EditText mSearchBoxEditText;

    private TextView mUrlDisplayTextView;

    private TextView mSearchResultsTextView;

    // COMPLETED (12) Create a variable to store a reference to the error message TextView
    private TextView mErrorMessageDisplay;

    // COMPLETED (24) Create a ProgressBar variable to store a reference to the ProgressBar
    private ProgressBar mLoadingIndicator;

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

        mSearchBoxEditText = (EditText) findViewById(R.id.et_search_box);

        mUrlDisplayTextView = (TextView) findViewById(R.id.tv_url_display);
        mSearchResultsTextView = (TextView) findViewById(R.id.tv_github_search_results_json);

        // COMPLETED (13) Get a reference to the error TextView using findViewById
        mErrorMessageDisplay = (TextView) findViewById(R.id.tv_error_message_display);

        // COMPLETED (25) Get a reference to the ProgressBar using findViewById
        mLoadingIndicator = (ProgressBar) findViewById(R.id.pb_loading_indicator);
    }

    /**
     * This method retrieves the search text from the EditText, constructs the
     * URL (using {@link NetworkUtils}) for the github repository you'd like to find, displays
     * that URL in a TextView, and finally fires off an AsyncTask to perform the GET request using
     * our {@link GithubQueryTask}
     */
    private void makeGithubSearchQuery() {
        String githubQuery = mSearchBoxEditText.getText().toString();
        URL githubSearchUrl = NetworkUtils.buildUrl(githubQuery);
        mUrlDisplayTextView.setText(githubSearchUrl.toString());
        new GithubQueryTask().execute(githubSearchUrl);
    }

    // COMPLETED (14) Create a method called showJsonDataView to show the data and hide the error
    /**
     * This method will make the View for the JSON data visible and
     * hide the error message.
     * <p>
     * Since it is okay to redundantly set the visibility of a View, we don't
     * need to check whether each view is currently visible or invisible.
     */
    private void showJsonDataView() {
        // First, make sure the error is invisible
        mErrorMessageDisplay.setVisibility(View.INVISIBLE);
        // Then, make sure the JSON data is visible
        mSearchResultsTextView.setVisibility(View.VISIBLE);
    }

    // COMPLETED (15) Create a method called showErrorMessage to show the error and hide the data
    /**
     * This method will make the error message visible and hide the JSON
     * View.
     * <p>
     * Since it is okay to redundantly set the visibility of a View, we don't
     * need to check whether each view is currently visible or invisible.
     */
    private void showErrorMessage() {
        // First, hide the currently visible data
        mSearchResultsTextView.setVisibility(View.INVISIBLE);
        // Then, show the error
        mErrorMessageDisplay.setVisibility(View.VISIBLE);
    }

    public class GithubQueryTask extends AsyncTask<URL, Void, String> {

        // COMPLETED (26) Override onPreExecute to set the loading indicator to visible
        @Override
        protected void onPreExecute() {
            super.onPreExecute();
            mLoadingIndicator.setVisibility(View.VISIBLE);
        }

        @Override
        protected String doInBackground(URL... params) {
            URL searchUrl = params[0];
            String githubSearchResults = null;
            try {
                githubSearchResults = NetworkUtils.getResponseFromHttpUrl(searchUrl);
            } catch (IOException e) {
                e.printStackTrace();
            }
            return githubSearchResults;
        }

        @Override
        protected void onPostExecute(String githubSearchResults) {
            // COMPLETED (27) As soon as the loading is complete, hide the loading indicator
            mLoadingIndicator.setVisibility(View.INVISIBLE);
            if (githubSearchResults != null && !githubSearchResults.equals("")) {
                // COMPLETED (17) Call showJsonDataView if we have valid, non-null results
                showJsonDataView();
                mSearchResultsTextView.setText(githubSearchResults);
            } else {
                // COMPLETED (16) Call showErrorMessage if the result is null in onPostExecute
                showErrorMessage();
            }
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int itemThatWasClickedId = item.getItemId();
        if (itemThatWasClickedId == R.id.action_search) {
            makeGithubSearchQuery();
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="com.example.android.datafrominternet">

    <!-- INTERNET PERMISSION -->
    <uses-permission android:name="android.permission.INTERNET" />

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name="com.example.android.datafrominternet.MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>

                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>
    </application>

</manifest>

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