add License activity (#689)

* convert AboutActivity to Kotlin, use BottomSheetActivity for account resolving

* improve AboutActivity

* new License activity

* fix filemojicompat url

app/src/main/java/com/keylesspalace/tusky/AboutActivity.kt

@@ -0,0 +1,87 @@
+package com.keylesspalace.tusky
+
+import android.content.Intent
+import android.os.Bundle
+import android.support.annotation.StringRes
+import android.text.SpannableString
+import android.text.SpannableStringBuilder
+import android.text.method.LinkMovementMethod
+import android.text.style.URLSpan
+import android.text.util.Linkify
+import android.view.MenuItem
+import android.widget.TextView
+import com.keylesspalace.tusky.di.Injectable
+import com.keylesspalace.tusky.util.CustomURLSpan
+import kotlinx.android.synthetic.main.activity_about.*
+import kotlinx.android.synthetic.main.toolbar_basic.*
+
+class AboutActivity : BottomSheetActivity(), Injectable {
+
+    override fun onCreate(savedInstanceState: Bundle?) {
+        super.onCreate(savedInstanceState)
+        setContentView(R.layout.activity_about)
+
+        setSupportActionBar(toolbar)
+        supportActionBar?.run {
+            setDisplayHomeAsUpEnabled(true)
+            setDisplayShowHomeEnabled(true)
+        }
+
+        setTitle(R.string.about_title_activity)
+
+        versionTextView.text = getString(R.string.about_tusky_version, BuildConfig.VERSION_NAME)
+
+        aboutLicenseInfoTextView.setClickableTextWithoutUnderlines(R.string.about_tusky_license)
+        aboutWebsiteInfoTextView.setClickableTextWithoutUnderlines(R.string.about_project_site)
+        aboutBugsFeaturesInfoTextView.setClickableTextWithoutUnderlines(R.string.about_bug_feature_request_site)
+
+        tuskyProfileButton.setOnClickListener {
+            onAccountButtonClick()
+        }
+
+        aboutLicensesButton.setOnClickListener {
+            startActivity(Intent(this, LicenseActivity::class.java))
+        }
+
+    }
+
+    private fun onAccountButtonClick() {
+        viewUrl("https://mastodon.social/@Tusky")
+    }
+
+    override fun onOptionsItemSelected(item: MenuItem): Boolean {
+        when (item.itemId) {
+            android.R.id.home -> {
+                onBackPressed()
+                return true
+            }
+        }
+        return super.onOptionsItemSelected(item)
+    }
+
+}
+
+private fun TextView.setClickableTextWithoutUnderlines(@StringRes textId: Int) {
+
+    val text = SpannableString(context.getText(textId))
+
+    Linkify.addLinks(text, Linkify.WEB_URLS)
+
+    val builder = SpannableStringBuilder(text)
+    val urlSpans = text.getSpans(0, text.length, URLSpan::class.java)
+    for (span in urlSpans) {
+        val start = builder.getSpanStart(span)
+        val end = builder.getSpanEnd(span)
+        val flags = builder.getSpanFlags(span)
+
+        val customSpan = object : CustomURLSpan(span.url) {}
+
+        builder.removeSpan(span)
+        builder.setSpan(customSpan, start, end, flags)
+    }
+
+    setText(builder)
+    linksClickable = true
+    movementMethod = LinkMovementMethod.getInstance()
+
+}