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Android lacks support for graph view. Here is my implementation of custom view showing bar chart. You can use this source file in your project. The view will appear like this. /* * Copyright (c) 2016, Swapnil Chaudhari. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A...

I had a project in eclipse which uses httpcomponents . The jars used in eclipse did not work in Android studio and I am using compileSdkVersion 23 with buildToolsVersion '23.0.2'. I have tried out several solutions and wasted 3 hours figuring out how import the httpcomponents libraries. To avoid wasting your time, here is how I fixed the issue: Changes in Module specific build.gradle i.e. /app/build.gradle Add following under android {...} useLibrary 'org.apache.http.legacy' packagingOptions { exclude 'META-INF/DEPENDENCIES' exclude 'META-INF/NOTICE' exclude 'META-INF/LICENSE' exclude 'META-INF/LICENSE.txt' exclude 'META-INF/NOTICE.txt' } Add following under dependencies {..} compile ('org.apache.httpcomponents:httpmime:4.3'){ exclude group: 'org.apache.httpcomponents', module: 'httpclient' } compile ('org.apache.httpcomponents:httpcore:4.4.1'){ exclude group: 'org.apache.htt...

Android studio uses new build system called Gradle. We can use it to build project and configure server urls, settings or replace assets. 1. Following example shows build.gradle file to change server url depending upon the build flavor. I am using two flavors 1. devel 2. prod. For simplicity I shall keep it simple without configuring it for signing. Both flavors define a config variable "HOST" with different value to be used, when apk is built. If developer chooses, to have "devel" build, it will come with "http://192.168.1.34:3000" as HOST. productFlavors { devel { buildConfigField 'String', 'HOST', '"http://192.168.1.34:3000"' } prod { buildConfigField 'String', 'HOST', '"http://api.zuul.com"' } } To access the config constant use following code. String string = BuildConfig.HOST; 2. Following example shows how t...

Following are the techniques to save data so that activity can resume from where it had destroyed. 1. onSaveInstanceState() You can save your serializable data in a bundle and android will save this bundle for you. The same bundle will be returned to you on on in onCreate() and onRestoreInstanceState() callback methods. onRestoreInstanceState() is called after onStart(), whereas onCreate() is called before onStart(). These methods are only called when needed, that is when an activity has been destroyed (because of lack of resources) and needs to be recreated by the system. Because the onCreate() method is called whether the system is creating a new instance of your activity or recreating a previous one, you must check whether the state Bundle is null before you attempt to read it. If it is null, then the system is creating a new instance of the activity, instead of restoring a previous one that was destroyed. e.g. @Override protected void onCreate(Bundle savedInstanceState) { ...

I wanted to try out installing the app wirelessly on device. I followed some links given below: 1. http://developer.android.com/tools/help/adb.html 2. http://stackoverflow.com/questions/2604727/how-can-i-connect-to-android-with-adb-over-tcp 3. https://docs.google.com/document/d/1-wMYWpljgHolnVHCsV2VGeMmBcc29Id9rMbHrZoCelE/edit# All of thes mentioned similar steps however none worked for me. Problem arised when following command was executed. d:\sdk\platform-tools>adb tcpip 5555 restarting in TCP mode port: 5555 The command seemed to be stuck and did not finish executing. It took 4-6 hours to figure out the correct procedure by trial and error. Here's the correct procedure. 1. Connect your phone to PC. 2. Open command prompt and go to /sdk/platform-tools/ directory. 3. Now type the following command " adb tcpip 5555". 4. Once you see "restarting ..." message, remove device from PC. This will finish execution of above command. D:\sdkForEclipse...

Recently I came across this post . It describes how to start working with new app ideas and make them market ready. It also mentions some tools to analyze competition of existing apps, prepare wireframes, server support. I hope you will find it useful too. For wireframes more free tools are available. These are mentioned in here .

As we have seen in earlier post first method to reduce memory was reducing font loading. This is described here . Next method is to use weak references. 2. Making use of weak references Our application uses observer model to notify data availability. Here a EventNotifier class is used to register listeners for the event. As soon as the event occurs, it fires the event with EventId and EventObject. Some activities use data that is fetched from server. In order to get this event activity registers itself with the EventNotifier. There is a communicator thread, which downloads data, and calls method public int eventNotify(int eventType, Object eventObject) of EventNotifier. Now this method finds out registered listeners and informs them about update. Problem comes when Android decides to kill activity for reusing resources. In this case OnDestroy() method may not get called. OnDestroy() handles unregistration activity from EventNotifier. Now as the EventNotifier still holds re...